xref: /petsc/src/dm/dt/dualspace/impls/lagrange/dspacelagrange.c (revision e91c04dfc8a52dee1965211bb1cc8e5bf775178f)
1 #include <petsc/private/petscfeimpl.h> /*I "petscfe.h" I*/
2 #include <petscdmplex.h>
3 #include <petscblaslapack.h>
4 
5 PetscErrorCode DMPlexGetTransitiveClosure_Internal(DM, PetscInt, PetscInt, PetscBool, PetscInt *, PetscInt *[]);
6 
7 struct _n_Petsc1DNodeFamily {
8   PetscInt        refct;
9   PetscDTNodeType nodeFamily;
10   PetscReal       gaussJacobiExp;
11   PetscInt        nComputed;
12   PetscReal     **nodesets;
13   PetscBool       endpoints;
14 };
15 
16 /* users set node families for PETSCDUALSPACELAGRANGE with just the inputs to this function, but internally we create
17  * an object that can cache the computations across multiple dual spaces */
18 static PetscErrorCode Petsc1DNodeFamilyCreate(PetscDTNodeType family, PetscReal gaussJacobiExp, PetscBool endpoints, Petsc1DNodeFamily *nf)
19 {
20   Petsc1DNodeFamily f;
21 
22   PetscFunctionBegin;
23   PetscCall(PetscNew(&f));
24   switch (family) {
25   case PETSCDTNODES_GAUSSJACOBI:
26   case PETSCDTNODES_EQUISPACED:
27     f->nodeFamily = family;
28     break;
29   default:
30     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Unknown 1D node family");
31   }
32   f->endpoints      = endpoints;
33   f->gaussJacobiExp = 0.;
34   if (family == PETSCDTNODES_GAUSSJACOBI) {
35     PetscCheck(gaussJacobiExp > -1., PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Gauss-Jacobi exponent must be > -1.");
36     f->gaussJacobiExp = gaussJacobiExp;
37   }
38   f->refct = 1;
39   *nf      = f;
40   PetscFunctionReturn(PETSC_SUCCESS);
41 }
42 
43 static PetscErrorCode Petsc1DNodeFamilyReference(Petsc1DNodeFamily nf)
44 {
45   PetscFunctionBegin;
46   if (nf) nf->refct++;
47   PetscFunctionReturn(PETSC_SUCCESS);
48 }
49 
50 static PetscErrorCode Petsc1DNodeFamilyDestroy(Petsc1DNodeFamily *nf)
51 {
52   PetscInt i, nc;
53 
54   PetscFunctionBegin;
55   if (!*nf) PetscFunctionReturn(PETSC_SUCCESS);
56   if (--(*nf)->refct > 0) {
57     *nf = NULL;
58     PetscFunctionReturn(PETSC_SUCCESS);
59   }
60   nc = (*nf)->nComputed;
61   for (i = 0; i < nc; i++) PetscCall(PetscFree((*nf)->nodesets[i]));
62   PetscCall(PetscFree((*nf)->nodesets));
63   PetscCall(PetscFree(*nf));
64   *nf = NULL;
65   PetscFunctionReturn(PETSC_SUCCESS);
66 }
67 
68 static PetscErrorCode Petsc1DNodeFamilyGetNodeSets(Petsc1DNodeFamily f, PetscInt degree, PetscReal ***nodesets)
69 {
70   PetscInt nc;
71 
72   PetscFunctionBegin;
73   nc = f->nComputed;
74   if (degree >= nc) {
75     PetscInt    i, j;
76     PetscReal **new_nodesets;
77     PetscReal  *w;
78 
79     PetscCall(PetscMalloc1(degree + 1, &new_nodesets));
80     PetscCall(PetscArraycpy(new_nodesets, f->nodesets, nc));
81     PetscCall(PetscFree(f->nodesets));
82     f->nodesets = new_nodesets;
83     PetscCall(PetscMalloc1(degree + 1, &w));
84     for (i = nc; i < degree + 1; i++) {
85       PetscCall(PetscMalloc1(i + 1, &f->nodesets[i]));
86       if (!i) {
87         f->nodesets[i][0] = 0.5;
88       } else {
89         switch (f->nodeFamily) {
90         case PETSCDTNODES_EQUISPACED:
91           if (f->endpoints) {
92             for (j = 0; j <= i; j++) f->nodesets[i][j] = (PetscReal)j / (PetscReal)i;
93           } else {
94             /* these nodes are at the centroids of the small simplices created by the equispaced nodes that include
95              * the endpoints */
96             for (j = 0; j <= i; j++) f->nodesets[i][j] = ((PetscReal)j + 0.5) / ((PetscReal)i + 1.);
97           }
98           break;
99         case PETSCDTNODES_GAUSSJACOBI:
100           if (f->endpoints) {
101             PetscCall(PetscDTGaussLobattoJacobiQuadrature(i + 1, 0., 1., f->gaussJacobiExp, f->gaussJacobiExp, f->nodesets[i], w));
102           } else {
103             PetscCall(PetscDTGaussJacobiQuadrature(i + 1, 0., 1., f->gaussJacobiExp, f->gaussJacobiExp, f->nodesets[i], w));
104           }
105           break;
106         default:
107           SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Unknown 1D node family");
108         }
109       }
110     }
111     PetscCall(PetscFree(w));
112     f->nComputed = degree + 1;
113   }
114   *nodesets = f->nodesets;
115   PetscFunctionReturn(PETSC_SUCCESS);
116 }
117 
118 /* http://arxiv.org/abs/2002.09421 for details */
119 static PetscErrorCode PetscNodeRecursive_Internal(PetscInt dim, PetscInt degree, PetscReal **nodesets, PetscInt tup[], PetscReal node[])
120 {
121   PetscReal w;
122   PetscInt  i, j;
123 
124   PetscFunctionBeginHot;
125   w = 0.;
126   if (dim == 1) {
127     node[0] = nodesets[degree][tup[0]];
128     node[1] = nodesets[degree][tup[1]];
129   } else {
130     for (i = 0; i < dim + 1; i++) node[i] = 0.;
131     for (i = 0; i < dim + 1; i++) {
132       PetscReal wi = nodesets[degree][degree - tup[i]];
133 
134       for (j = 0; j < dim + 1; j++) tup[dim + 1 + j] = tup[j + (j >= i)];
135       PetscCall(PetscNodeRecursive_Internal(dim - 1, degree - tup[i], nodesets, &tup[dim + 1], &node[dim + 1]));
136       for (j = 0; j < dim + 1; j++) node[j + (j >= i)] += wi * node[dim + 1 + j];
137       w += wi;
138     }
139     for (i = 0; i < dim + 1; i++) node[i] /= w;
140   }
141   PetscFunctionReturn(PETSC_SUCCESS);
142 }
143 
144 /* compute simplex nodes for the biunit simplex from the 1D node family */
145 static PetscErrorCode Petsc1DNodeFamilyComputeSimplexNodes(Petsc1DNodeFamily f, PetscInt dim, PetscInt degree, PetscReal points[])
146 {
147   PetscInt   *tup;
148   PetscInt    npoints;
149   PetscReal **nodesets = NULL;
150   PetscInt    worksize;
151   PetscReal  *nodework;
152   PetscInt   *tupwork;
153 
154   PetscFunctionBegin;
155   PetscCheck(dim >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Must have non-negative dimension");
156   PetscCheck(degree >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Must have non-negative degree");
157   if (!dim) PetscFunctionReturn(PETSC_SUCCESS);
158   PetscCall(PetscCalloc1(dim + 2, &tup));
159   PetscCall(PetscDTBinomialInt(degree + dim, dim, &npoints));
160   PetscCall(Petsc1DNodeFamilyGetNodeSets(f, degree, &nodesets));
161   worksize = ((dim + 2) * (dim + 3)) / 2;
162   PetscCall(PetscCalloc2(worksize, &nodework, worksize, &tupwork));
163   /* loop over the tuples of length dim with sum at most degree */
164   for (PetscInt k = 0; k < npoints; k++) {
165     PetscInt i;
166 
167     /* turn thm into tuples of length dim + 1 with sum equal to degree (barycentric indice) */
168     tup[0] = degree;
169     for (i = 0; i < dim; i++) tup[0] -= tup[i + 1];
170     switch (f->nodeFamily) {
171     case PETSCDTNODES_EQUISPACED:
172       /* compute equispaces nodes on the unit reference triangle */
173       if (f->endpoints) {
174         PetscCheck(degree > 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Must have positive degree");
175         for (i = 0; i < dim; i++) points[dim * k + i] = (PetscReal)tup[i + 1] / (PetscReal)degree;
176       } else {
177         for (i = 0; i < dim; i++) {
178           /* these nodes are at the centroids of the small simplices created by the equispaced nodes that include
179            * the endpoints */
180           points[dim * k + i] = ((PetscReal)tup[i + 1] + 1. / (dim + 1.)) / (PetscReal)(degree + 1.);
181         }
182       }
183       break;
184     default:
185       /* compute equispaced nodes on the barycentric reference triangle (the trace on the first dim dimensions are the
186        * unit reference triangle nodes */
187       for (i = 0; i < dim + 1; i++) tupwork[i] = tup[i];
188       PetscCall(PetscNodeRecursive_Internal(dim, degree, nodesets, tupwork, nodework));
189       for (i = 0; i < dim; i++) points[dim * k + i] = nodework[i + 1];
190       break;
191     }
192     PetscCall(PetscDualSpaceLatticePointLexicographic_Internal(dim, degree, &tup[1]));
193   }
194   /* map from unit simplex to biunit simplex */
195   for (PetscInt k = 0; k < npoints * dim; k++) points[k] = points[k] * 2. - 1.;
196   PetscCall(PetscFree2(nodework, tupwork));
197   PetscCall(PetscFree(tup));
198   PetscFunctionReturn(PETSC_SUCCESS);
199 }
200 
201 /* If we need to get the dofs from a mesh point, or add values into dofs at a mesh point, and there is more than one dof
202  * on that mesh point, we have to be careful about getting/adding everything in the right place.
203  *
204  * With nodal dofs like PETSCDUALSPACELAGRANGE makes, the general approach to calculate the value of dofs associate
205  * with a node A is
206  * - transform the node locations x(A) by the map that takes the mesh point to its reorientation, x' = phi(x(A))
207  * - figure out which node was originally at the location of the transformed point, A' = idx(x')
208  * - if the dofs are not scalars, figure out how to represent the transformed dofs in terms of the basis
209  *   of dofs at A' (using pushforward/pullback rules)
210  *
211  * The one sticky point with this approach is the "A' = idx(x')" step: trying to go from real valued coordinates
212  * back to indices.  I don't want to rely on floating point tolerances.  Additionally, PETSCDUALSPACELAGRANGE may
213  * eventually support quasi-Lagrangian dofs, which could involve quadrature at multiple points, so the location "x(A)"
214  * would be ambiguous.
215  *
216  * So each dof gets an integer value coordinate (nodeIdx in the structure below).  The choice of integer coordinates
217  * is somewhat arbitrary, as long as all of the relevant symmetries of the mesh point correspond to *permutations* of
218  * the integer coordinates, which do not depend on numerical precision.
219  *
220  * So
221  *
222  * - DMPlexGetTransitiveClosure_Internal() tells me how an orientation turns into a permutation of the vertices of a
223  *   mesh point
224  * - The permutation of the vertices, and the nodeIdx values assigned to them, tells what permutation in index space
225  *   is associated with the orientation
226  * - I uses that permutation to get xi' = phi(xi(A)), the integer coordinate of the transformed dof
227  * - I can without numerical issues compute A' = idx(xi')
228  *
229  * Here are some examples of how the process works
230  *
231  * - With a triangle:
232  *
233  *   The triangle has the following integer coordinates for vertices, taken from the barycentric triangle
234  *
235  *     closure order 2
236  *     nodeIdx (0,0,1)
237  *      \
238  *       +
239  *       |\
240  *       | \
241  *       |  \
242  *       |   \    closure order 1
243  *       |    \ / nodeIdx (0,1,0)
244  *       +-----+
245  *        \
246  *      closure order 0
247  *      nodeIdx (1,0,0)
248  *
249  *   If I do DMPlexGetTransitiveClosure_Internal() with orientation 1, the vertices would appear
250  *   in the order (1, 2, 0)
251  *
252  *   If I list the nodeIdx of each vertex in closure order for orientation 0 (0, 1, 2) and orientation 1 (1, 2, 0), I
253  *   see
254  *
255  *   orientation 0  | orientation 1
256  *
257  *   [0] (1,0,0)      [1] (0,1,0)
258  *   [1] (0,1,0)      [2] (0,0,1)
259  *   [2] (0,0,1)      [0] (1,0,0)
260  *          A                B
261  *
262  *   In other words, B is the result of a row permutation of A.  But, there is also
263  *   a column permutation that accomplishes the same result, (2,0,1).
264  *
265  *   So if a dof has nodeIdx coordinate (a,b,c), after the transformation its nodeIdx coordinate
266  *   is (c,a,b), and the transformed degree of freedom will be a linear combination of dofs
267  *   that originally had coordinate (c,a,b).
268  *
269  * - With a quadrilateral:
270  *
271  *   The quadrilateral has the following integer coordinates for vertices, taken from concatenating barycentric
272  *   coordinates for two segments:
273  *
274  *     closure order 3      closure order 2
275  *     nodeIdx (1,0,0,1)    nodeIdx (0,1,0,1)
276  *                   \      /
277  *                    +----+
278  *                    |    |
279  *                    |    |
280  *                    +----+
281  *                   /      \
282  *     closure order 0      closure order 1
283  *     nodeIdx (1,0,1,0)    nodeIdx (0,1,1,0)
284  *
285  *   If I do DMPlexGetTransitiveClosure_Internal() with orientation 1, the vertices would appear
286  *   in the order (1, 2, 3, 0)
287  *
288  *   If I list the nodeIdx of each vertex in closure order for orientation 0 (0, 1, 2, 3) and
289  *   orientation 1 (1, 2, 3, 0), I see
290  *
291  *   orientation 0  | orientation 1
292  *
293  *   [0] (1,0,1,0)    [1] (0,1,1,0)
294  *   [1] (0,1,1,0)    [2] (0,1,0,1)
295  *   [2] (0,1,0,1)    [3] (1,0,0,1)
296  *   [3] (1,0,0,1)    [0] (1,0,1,0)
297  *          A                B
298  *
299  *   The column permutation that accomplishes the same result is (3,2,0,1).
300  *
301  *   So if a dof has nodeIdx coordinate (a,b,c,d), after the transformation its nodeIdx coordinate
302  *   is (d,c,a,b), and the transformed degree of freedom will be a linear combination of dofs
303  *   that originally had coordinate (d,c,a,b).
304  *
305  * Previously PETSCDUALSPACELAGRANGE had hardcoded symmetries for the triangle and quadrilateral,
306  * but this approach will work for any polytope, such as the wedge (triangular prism).
307  */
308 struct _n_PetscLagNodeIndices {
309   PetscInt   refct;
310   PetscInt   nodeIdxDim;
311   PetscInt   nodeVecDim;
312   PetscInt   nNodes;
313   PetscInt  *nodeIdx; /* for each node an index of size nodeIdxDim */
314   PetscReal *nodeVec; /* for each node a vector of size nodeVecDim */
315   PetscInt  *perm;    /* if these are vertices, perm takes DMPlex point index to closure order;
316                               if these are nodes, perm lists nodes in index revlex order */
317 };
318 
319 /* this is just here so I can access the values in tests/ex1.c outside the library */
320 PetscErrorCode PetscLagNodeIndicesGetData_Internal(PetscLagNodeIndices ni, PetscInt *nodeIdxDim, PetscInt *nodeVecDim, PetscInt *nNodes, const PetscInt *nodeIdx[], const PetscReal *nodeVec[])
321 {
322   PetscFunctionBegin;
323   *nodeIdxDim = ni->nodeIdxDim;
324   *nodeVecDim = ni->nodeVecDim;
325   *nNodes     = ni->nNodes;
326   *nodeIdx    = ni->nodeIdx;
327   *nodeVec    = ni->nodeVec;
328   PetscFunctionReturn(PETSC_SUCCESS);
329 }
330 
331 static PetscErrorCode PetscLagNodeIndicesReference(PetscLagNodeIndices ni)
332 {
333   PetscFunctionBegin;
334   if (ni) ni->refct++;
335   PetscFunctionReturn(PETSC_SUCCESS);
336 }
337 
338 static PetscErrorCode PetscLagNodeIndicesDuplicate(PetscLagNodeIndices ni, PetscLagNodeIndices *niNew)
339 {
340   PetscFunctionBegin;
341   PetscCall(PetscNew(niNew));
342   (*niNew)->refct      = 1;
343   (*niNew)->nodeIdxDim = ni->nodeIdxDim;
344   (*niNew)->nodeVecDim = ni->nodeVecDim;
345   (*niNew)->nNodes     = ni->nNodes;
346   PetscCall(PetscMalloc1(ni->nNodes * ni->nodeIdxDim, &((*niNew)->nodeIdx)));
347   PetscCall(PetscArraycpy((*niNew)->nodeIdx, ni->nodeIdx, ni->nNodes * ni->nodeIdxDim));
348   PetscCall(PetscMalloc1(ni->nNodes * ni->nodeVecDim, &((*niNew)->nodeVec)));
349   PetscCall(PetscArraycpy((*niNew)->nodeVec, ni->nodeVec, ni->nNodes * ni->nodeVecDim));
350   (*niNew)->perm = NULL;
351   PetscFunctionReturn(PETSC_SUCCESS);
352 }
353 
354 static PetscErrorCode PetscLagNodeIndicesDestroy(PetscLagNodeIndices *ni)
355 {
356   PetscFunctionBegin;
357   if (!*ni) PetscFunctionReturn(PETSC_SUCCESS);
358   if (--(*ni)->refct > 0) {
359     *ni = NULL;
360     PetscFunctionReturn(PETSC_SUCCESS);
361   }
362   PetscCall(PetscFree((*ni)->nodeIdx));
363   PetscCall(PetscFree((*ni)->nodeVec));
364   PetscCall(PetscFree((*ni)->perm));
365   PetscCall(PetscFree(*ni));
366   *ni = NULL;
367   PetscFunctionReturn(PETSC_SUCCESS);
368 }
369 
370 /* The vertices are given nodeIdx coordinates (e.g. the corners of the barycentric triangle).  Those coordinates are
371  * in some other order, and to understand the effect of different symmetries, we need them to be in closure order.
372  *
373  * If sortIdx is PETSC_FALSE, the coordinates are already in revlex order, otherwise we must sort them
374  * to that order before we do the real work of this function, which is
375  *
376  * - mark the vertices in closure order
377  * - sort them in revlex order
378  * - use the resulting permutation to list the vertex coordinates in closure order
379  */
380 static PetscErrorCode PetscLagNodeIndicesComputeVertexOrder(DM dm, PetscLagNodeIndices ni, PetscBool sortIdx)
381 {
382   PetscInt           v, w, vStart, vEnd, c, d;
383   PetscInt           nVerts;
384   PetscInt           closureSize = 0;
385   PetscInt          *closure     = NULL;
386   PetscInt          *closureOrder;
387   PetscInt          *invClosureOrder;
388   PetscInt          *revlexOrder;
389   PetscInt          *newNodeIdx;
390   PetscInt           dim;
391   Vec                coordVec;
392   const PetscScalar *coords;
393 
394   PetscFunctionBegin;
395   PetscCall(DMGetDimension(dm, &dim));
396   PetscCall(DMPlexGetDepthStratum(dm, 0, &vStart, &vEnd));
397   nVerts = vEnd - vStart;
398   PetscCall(PetscMalloc1(nVerts, &closureOrder));
399   PetscCall(PetscMalloc1(nVerts, &invClosureOrder));
400   PetscCall(PetscMalloc1(nVerts, &revlexOrder));
401   if (sortIdx) { /* bubble sort nodeIdx into revlex order */
402     PetscInt  nodeIdxDim = ni->nodeIdxDim;
403     PetscInt *idxOrder;
404 
405     PetscCall(PetscMalloc1(nVerts * nodeIdxDim, &newNodeIdx));
406     PetscCall(PetscMalloc1(nVerts, &idxOrder));
407     for (v = 0; v < nVerts; v++) idxOrder[v] = v;
408     for (v = 0; v < nVerts; v++) {
409       for (w = v + 1; w < nVerts; w++) {
410         const PetscInt *iv   = &(ni->nodeIdx[idxOrder[v] * nodeIdxDim]);
411         const PetscInt *iw   = &(ni->nodeIdx[idxOrder[w] * nodeIdxDim]);
412         PetscInt        diff = 0;
413 
414         for (d = nodeIdxDim - 1; d >= 0; d--)
415           if ((diff = (iv[d] - iw[d]))) break;
416         if (diff > 0) {
417           PetscInt swap = idxOrder[v];
418 
419           idxOrder[v] = idxOrder[w];
420           idxOrder[w] = swap;
421         }
422       }
423     }
424     for (v = 0; v < nVerts; v++) {
425       for (d = 0; d < nodeIdxDim; d++) newNodeIdx[v * ni->nodeIdxDim + d] = ni->nodeIdx[idxOrder[v] * nodeIdxDim + d];
426     }
427     PetscCall(PetscFree(ni->nodeIdx));
428     ni->nodeIdx = newNodeIdx;
429     newNodeIdx  = NULL;
430     PetscCall(PetscFree(idxOrder));
431   }
432   PetscCall(DMPlexGetTransitiveClosure(dm, 0, PETSC_TRUE, &closureSize, &closure));
433   c = closureSize - nVerts;
434   for (v = 0; v < nVerts; v++) closureOrder[v] = closure[2 * (c + v)] - vStart;
435   for (v = 0; v < nVerts; v++) invClosureOrder[closureOrder[v]] = v;
436   PetscCall(DMPlexRestoreTransitiveClosure(dm, 0, PETSC_TRUE, &closureSize, &closure));
437   PetscCall(DMGetCoordinatesLocal(dm, &coordVec));
438   PetscCall(VecGetArrayRead(coordVec, &coords));
439   /* bubble sort closure vertices by coordinates in revlex order */
440   for (v = 0; v < nVerts; v++) revlexOrder[v] = v;
441   for (v = 0; v < nVerts; v++) {
442     for (w = v + 1; w < nVerts; w++) {
443       const PetscScalar *cv   = &coords[closureOrder[revlexOrder[v]] * dim];
444       const PetscScalar *cw   = &coords[closureOrder[revlexOrder[w]] * dim];
445       PetscReal          diff = 0;
446 
447       for (d = dim - 1; d >= 0; d--)
448         if ((diff = PetscRealPart(cv[d] - cw[d])) != 0.) break;
449       if (diff > 0.) {
450         PetscInt swap = revlexOrder[v];
451 
452         revlexOrder[v] = revlexOrder[w];
453         revlexOrder[w] = swap;
454       }
455     }
456   }
457   PetscCall(VecRestoreArrayRead(coordVec, &coords));
458   PetscCall(PetscMalloc1(ni->nodeIdxDim * nVerts, &newNodeIdx));
459   /* reorder nodeIdx to be in closure order */
460   for (v = 0; v < nVerts; v++) {
461     for (d = 0; d < ni->nodeIdxDim; d++) newNodeIdx[revlexOrder[v] * ni->nodeIdxDim + d] = ni->nodeIdx[v * ni->nodeIdxDim + d];
462   }
463   PetscCall(PetscFree(ni->nodeIdx));
464   ni->nodeIdx = newNodeIdx;
465   ni->perm    = invClosureOrder;
466   PetscCall(PetscFree(revlexOrder));
467   PetscCall(PetscFree(closureOrder));
468   PetscFunctionReturn(PETSC_SUCCESS);
469 }
470 
471 /* the coordinates of the simplex vertices are the corners of the barycentric simplex.
472  * When we stack them on top of each other in revlex order, they look like the identity matrix */
473 static PetscErrorCode PetscLagNodeIndicesCreateSimplexVertices(DM dm, PetscLagNodeIndices *nodeIndices)
474 {
475   PetscLagNodeIndices ni;
476   PetscInt            dim, d;
477 
478   PetscFunctionBegin;
479   PetscCall(PetscNew(&ni));
480   PetscCall(DMGetDimension(dm, &dim));
481   ni->nodeIdxDim = dim + 1;
482   ni->nodeVecDim = 0;
483   ni->nNodes     = dim + 1;
484   ni->refct      = 1;
485   PetscCall(PetscCalloc1((dim + 1) * (dim + 1), &ni->nodeIdx));
486   for (d = 0; d < dim + 1; d++) ni->nodeIdx[d * (dim + 2)] = 1;
487   PetscCall(PetscLagNodeIndicesComputeVertexOrder(dm, ni, PETSC_FALSE));
488   *nodeIndices = ni;
489   PetscFunctionReturn(PETSC_SUCCESS);
490 }
491 
492 /* A polytope that is a tensor product of a facet and a segment.
493  * We take whatever coordinate system was being used for the facet
494  * and we concatenate the barycentric coordinates for the vertices
495  * at the end of the segment, (1,0) and (0,1), to get a coordinate
496  * system for the tensor product element */
497 static PetscErrorCode PetscLagNodeIndicesCreateTensorVertices(DM dm, PetscLagNodeIndices facetni, PetscLagNodeIndices *nodeIndices)
498 {
499   PetscLagNodeIndices ni;
500   PetscInt            nodeIdxDim, subNodeIdxDim = facetni->nodeIdxDim;
501   PetscInt            nVerts, nSubVerts         = facetni->nNodes;
502   PetscInt            dim, d, e, f, g;
503 
504   PetscFunctionBegin;
505   PetscCall(PetscNew(&ni));
506   PetscCall(DMGetDimension(dm, &dim));
507   ni->nodeIdxDim = nodeIdxDim = subNodeIdxDim + 2;
508   ni->nodeVecDim              = 0;
509   ni->nNodes = nVerts = 2 * nSubVerts;
510   ni->refct           = 1;
511   PetscCall(PetscCalloc1(nodeIdxDim * nVerts, &ni->nodeIdx));
512   for (f = 0, d = 0; d < 2; d++) {
513     for (e = 0; e < nSubVerts; e++, f++) {
514       for (g = 0; g < subNodeIdxDim; g++) ni->nodeIdx[f * nodeIdxDim + g] = facetni->nodeIdx[e * subNodeIdxDim + g];
515       ni->nodeIdx[f * nodeIdxDim + subNodeIdxDim]     = (1 - d);
516       ni->nodeIdx[f * nodeIdxDim + subNodeIdxDim + 1] = d;
517     }
518   }
519   PetscCall(PetscLagNodeIndicesComputeVertexOrder(dm, ni, PETSC_TRUE));
520   *nodeIndices = ni;
521   PetscFunctionReturn(PETSC_SUCCESS);
522 }
523 
524 /* This helps us compute symmetries, and it also helps us compute coordinates for dofs that are being pushed
525  * forward from a boundary mesh point.
526  *
527  * Input:
528  *
529  * dm - the target reference cell where we want new coordinates and dof directions to be valid
530  * vert - the vertex coordinate system for the target reference cell
531  * p - the point in the target reference cell that the dofs are coming from
532  * vertp - the vertex coordinate system for p's reference cell
533  * ornt - the resulting coordinates and dof vectors will be for p under this orientation
534  * nodep - the node coordinates and dof vectors in p's reference cell
535  * formDegree - the form degree that the dofs transform as
536  *
537  * Output:
538  *
539  * pfNodeIdx - the node coordinates for p's dofs, in the dm reference cell, from the ornt perspective
540  * pfNodeVec - the node dof vectors for p's dofs, in the dm reference cell, from the ornt perspective
541  */
542 static PetscErrorCode PetscLagNodeIndicesPushForward(DM dm, PetscLagNodeIndices vert, PetscInt p, PetscLagNodeIndices vertp, PetscLagNodeIndices nodep, PetscInt ornt, PetscInt formDegree, PetscInt pfNodeIdx[], PetscReal pfNodeVec[])
543 {
544   PetscInt          *closureVerts;
545   PetscInt           closureSize = 0;
546   PetscInt          *closure     = NULL;
547   PetscInt           dim, pdim, c, i, j, k, n, v, vStart, vEnd;
548   PetscInt           nSubVert      = vertp->nNodes;
549   PetscInt           nodeIdxDim    = vert->nodeIdxDim;
550   PetscInt           subNodeIdxDim = vertp->nodeIdxDim;
551   PetscInt           nNodes        = nodep->nNodes;
552   const PetscInt    *vertIdx       = vert->nodeIdx;
553   const PetscInt    *subVertIdx    = vertp->nodeIdx;
554   const PetscInt    *nodeIdx       = nodep->nodeIdx;
555   const PetscReal   *nodeVec       = nodep->nodeVec;
556   PetscReal         *J, *Jstar;
557   PetscReal          detJ;
558   PetscInt           depth, pdepth, Nk, pNk;
559   Vec                coordVec;
560   PetscScalar       *newCoords = NULL;
561   const PetscScalar *oldCoords = NULL;
562 
563   PetscFunctionBegin;
564   PetscCall(DMGetDimension(dm, &dim));
565   PetscCall(DMPlexGetDepth(dm, &depth));
566   PetscCall(DMGetCoordinatesLocal(dm, &coordVec));
567   PetscCall(DMPlexGetPointDepth(dm, p, &pdepth));
568   pdim = pdepth != depth ? pdepth != 0 ? pdepth : 0 : dim;
569   PetscCall(DMPlexGetDepthStratum(dm, 0, &vStart, &vEnd));
570   PetscCall(DMGetWorkArray(dm, nSubVert, MPIU_INT, &closureVerts));
571   PetscCall(DMPlexGetTransitiveClosure_Internal(dm, p, ornt, PETSC_TRUE, &closureSize, &closure));
572   c = closureSize - nSubVert;
573   /* we want which cell closure indices the closure of this point corresponds to */
574   for (v = 0; v < nSubVert; v++) closureVerts[v] = vert->perm[closure[2 * (c + v)] - vStart];
575   PetscCall(DMPlexRestoreTransitiveClosure(dm, p, PETSC_TRUE, &closureSize, &closure));
576   /* push forward indices */
577   for (i = 0; i < nodeIdxDim; i++) { /* for every component of the target index space */
578     /* check if this is a component that all vertices around this point have in common */
579     for (j = 1; j < nSubVert; j++) {
580       if (vertIdx[closureVerts[j] * nodeIdxDim + i] != vertIdx[closureVerts[0] * nodeIdxDim + i]) break;
581     }
582     if (j == nSubVert) { /* all vertices have this component in common, directly copy to output */
583       PetscInt val = vertIdx[closureVerts[0] * nodeIdxDim + i];
584       for (n = 0; n < nNodes; n++) pfNodeIdx[n * nodeIdxDim + i] = val;
585     } else {
586       PetscInt subi = -1;
587       /* there must be a component in vertp that looks the same */
588       for (k = 0; k < subNodeIdxDim; k++) {
589         for (j = 0; j < nSubVert; j++) {
590           if (vertIdx[closureVerts[j] * nodeIdxDim + i] != subVertIdx[j * subNodeIdxDim + k]) break;
591         }
592         if (j == nSubVert) {
593           subi = k;
594           break;
595         }
596       }
597       PetscCheck(subi >= 0, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Did not find matching coordinate");
598       /* that component in the vertp system becomes component i in the vert system for each dof */
599       for (n = 0; n < nNodes; n++) pfNodeIdx[n * nodeIdxDim + i] = nodeIdx[n * subNodeIdxDim + subi];
600     }
601   }
602   /* push forward vectors */
603   PetscCall(DMGetWorkArray(dm, dim * dim, MPIU_REAL, &J));
604   if (ornt != 0) { /* temporarily change the coordinate vector so
605                       DMPlexComputeCellGeometryAffineFEM gives us the Jacobian we want */
606     PetscInt  closureSize2 = 0;
607     PetscInt *closure2     = NULL;
608 
609     PetscCall(DMPlexGetTransitiveClosure_Internal(dm, p, 0, PETSC_TRUE, &closureSize2, &closure2));
610     PetscCall(PetscMalloc1(dim * nSubVert, &newCoords));
611     PetscCall(VecGetArrayRead(coordVec, &oldCoords));
612     for (v = 0; v < nSubVert; v++) {
613       PetscInt d;
614       for (d = 0; d < dim; d++) newCoords[(closure2[2 * (c + v)] - vStart) * dim + d] = oldCoords[closureVerts[v] * dim + d];
615     }
616     PetscCall(VecRestoreArrayRead(coordVec, &oldCoords));
617     PetscCall(DMPlexRestoreTransitiveClosure(dm, p, PETSC_TRUE, &closureSize2, &closure2));
618     PetscCall(VecPlaceArray(coordVec, newCoords));
619   }
620   PetscCall(DMPlexComputeCellGeometryAffineFEM(dm, p, NULL, J, NULL, &detJ));
621   if (ornt != 0) {
622     PetscCall(VecResetArray(coordVec));
623     PetscCall(PetscFree(newCoords));
624   }
625   PetscCall(DMRestoreWorkArray(dm, nSubVert, MPIU_INT, &closureVerts));
626   /* compactify */
627   for (i = 0; i < dim; i++)
628     for (j = 0; j < pdim; j++) J[i * pdim + j] = J[i * dim + j];
629   /* We have the Jacobian mapping the point's reference cell to this reference cell:
630    * pulling back a function to the point and applying the dof is what we want,
631    * so we get the pullback matrix and multiply the dof by that matrix on the right */
632   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(formDegree), &Nk));
633   PetscCall(PetscDTBinomialInt(pdim, PetscAbsInt(formDegree), &pNk));
634   PetscCall(DMGetWorkArray(dm, pNk * Nk, MPIU_REAL, &Jstar));
635   PetscCall(PetscDTAltVPullbackMatrix(pdim, dim, J, formDegree, Jstar));
636   for (n = 0; n < nNodes; n++) {
637     for (i = 0; i < Nk; i++) {
638       PetscReal val = 0.;
639       for (j = 0; j < pNk; j++) val += nodeVec[n * pNk + j] * Jstar[j * Nk + i];
640       pfNodeVec[n * Nk + i] = val;
641     }
642   }
643   PetscCall(DMRestoreWorkArray(dm, pNk * Nk, MPIU_REAL, &Jstar));
644   PetscCall(DMRestoreWorkArray(dm, dim * dim, MPIU_REAL, &J));
645   PetscFunctionReturn(PETSC_SUCCESS);
646 }
647 
648 /* given to sets of nodes, take the tensor product, where the product of the dof indices is concatenation and the
649  * product of the dof vectors is the wedge product */
650 static PetscErrorCode PetscLagNodeIndicesTensor(PetscLagNodeIndices tracei, PetscInt dimT, PetscInt kT, PetscLagNodeIndices fiberi, PetscInt dimF, PetscInt kF, PetscLagNodeIndices *nodeIndices)
651 {
652   PetscInt            dim = dimT + dimF;
653   PetscInt            nodeIdxDim, nNodes;
654   PetscInt            formDegree = kT + kF;
655   PetscInt            Nk, NkT, NkF;
656   PetscInt            MkT, MkF;
657   PetscLagNodeIndices ni;
658   PetscInt            i, j, l;
659   PetscReal          *projF, *projT;
660   PetscReal          *projFstar, *projTstar;
661   PetscReal          *workF, *workF2, *workT, *workT2, *work, *work2;
662   PetscReal          *wedgeMat;
663   PetscReal           sign;
664 
665   PetscFunctionBegin;
666   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(formDegree), &Nk));
667   PetscCall(PetscDTBinomialInt(dimT, PetscAbsInt(kT), &NkT));
668   PetscCall(PetscDTBinomialInt(dimF, PetscAbsInt(kF), &NkF));
669   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(kT), &MkT));
670   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(kF), &MkF));
671   PetscCall(PetscNew(&ni));
672   ni->nodeIdxDim = nodeIdxDim = tracei->nodeIdxDim + fiberi->nodeIdxDim;
673   ni->nodeVecDim              = Nk;
674   ni->nNodes = nNodes = tracei->nNodes * fiberi->nNodes;
675   ni->refct           = 1;
676   PetscCall(PetscMalloc1(nNodes * nodeIdxDim, &ni->nodeIdx));
677   /* first concatenate the indices */
678   for (l = 0, j = 0; j < fiberi->nNodes; j++) {
679     for (i = 0; i < tracei->nNodes; i++, l++) {
680       PetscInt m, n = 0;
681 
682       for (m = 0; m < tracei->nodeIdxDim; m++) ni->nodeIdx[l * nodeIdxDim + n++] = tracei->nodeIdx[i * tracei->nodeIdxDim + m];
683       for (m = 0; m < fiberi->nodeIdxDim; m++) ni->nodeIdx[l * nodeIdxDim + n++] = fiberi->nodeIdx[j * fiberi->nodeIdxDim + m];
684     }
685   }
686 
687   /* now wedge together the push-forward vectors */
688   PetscCall(PetscMalloc1(nNodes * Nk, &ni->nodeVec));
689   PetscCall(PetscCalloc2(dimT * dim, &projT, dimF * dim, &projF));
690   for (i = 0; i < dimT; i++) projT[i * (dim + 1)] = 1.;
691   for (i = 0; i < dimF; i++) projF[i * (dim + dimT + 1) + dimT] = 1.;
692   PetscCall(PetscMalloc2(MkT * NkT, &projTstar, MkF * NkF, &projFstar));
693   PetscCall(PetscDTAltVPullbackMatrix(dim, dimT, projT, kT, projTstar));
694   PetscCall(PetscDTAltVPullbackMatrix(dim, dimF, projF, kF, projFstar));
695   PetscCall(PetscMalloc6(MkT, &workT, MkT, &workT2, MkF, &workF, MkF, &workF2, Nk, &work, Nk, &work2));
696   PetscCall(PetscMalloc1(Nk * MkT, &wedgeMat));
697   sign = (PetscAbsInt(kT * kF) & 1) ? -1. : 1.;
698   for (l = 0, j = 0; j < fiberi->nNodes; j++) {
699     PetscInt d, e;
700 
701     /* push forward fiber k-form */
702     for (d = 0; d < MkF; d++) {
703       PetscReal val = 0.;
704       for (e = 0; e < NkF; e++) val += projFstar[d * NkF + e] * fiberi->nodeVec[j * NkF + e];
705       workF[d] = val;
706     }
707     /* Hodge star to proper form if necessary */
708     if (kF < 0) {
709       for (d = 0; d < MkF; d++) workF2[d] = workF[d];
710       PetscCall(PetscDTAltVStar(dim, PetscAbsInt(kF), 1, workF2, workF));
711     }
712     /* Compute the matrix that wedges this form with one of the trace k-form */
713     PetscCall(PetscDTAltVWedgeMatrix(dim, PetscAbsInt(kF), PetscAbsInt(kT), workF, wedgeMat));
714     for (i = 0; i < tracei->nNodes; i++, l++) {
715       /* push forward trace k-form */
716       for (d = 0; d < MkT; d++) {
717         PetscReal val = 0.;
718         for (e = 0; e < NkT; e++) val += projTstar[d * NkT + e] * tracei->nodeVec[i * NkT + e];
719         workT[d] = val;
720       }
721       /* Hodge star to proper form if necessary */
722       if (kT < 0) {
723         for (d = 0; d < MkT; d++) workT2[d] = workT[d];
724         PetscCall(PetscDTAltVStar(dim, PetscAbsInt(kT), 1, workT2, workT));
725       }
726       /* compute the wedge product of the push-forward trace form and firer forms */
727       for (d = 0; d < Nk; d++) {
728         PetscReal val = 0.;
729         for (e = 0; e < MkT; e++) val += wedgeMat[d * MkT + e] * workT[e];
730         work[d] = val;
731       }
732       /* inverse Hodge star from proper form if necessary */
733       if (formDegree < 0) {
734         for (d = 0; d < Nk; d++) work2[d] = work[d];
735         PetscCall(PetscDTAltVStar(dim, PetscAbsInt(formDegree), -1, work2, work));
736       }
737       /* insert into the array (adjusting for sign) */
738       for (d = 0; d < Nk; d++) ni->nodeVec[l * Nk + d] = sign * work[d];
739     }
740   }
741   PetscCall(PetscFree(wedgeMat));
742   PetscCall(PetscFree6(workT, workT2, workF, workF2, work, work2));
743   PetscCall(PetscFree2(projTstar, projFstar));
744   PetscCall(PetscFree2(projT, projF));
745   *nodeIndices = ni;
746   PetscFunctionReturn(PETSC_SUCCESS);
747 }
748 
749 /* simple union of two sets of nodes */
750 static PetscErrorCode PetscLagNodeIndicesMerge(PetscLagNodeIndices niA, PetscLagNodeIndices niB, PetscLagNodeIndices *nodeIndices)
751 {
752   PetscLagNodeIndices ni;
753   PetscInt            nodeIdxDim, nodeVecDim, nNodes;
754 
755   PetscFunctionBegin;
756   PetscCall(PetscNew(&ni));
757   ni->nodeIdxDim = nodeIdxDim = niA->nodeIdxDim;
758   PetscCheck(niB->nodeIdxDim == nodeIdxDim, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Cannot merge PetscLagNodeIndices with different nodeIdxDim");
759   ni->nodeVecDim = nodeVecDim = niA->nodeVecDim;
760   PetscCheck(niB->nodeVecDim == nodeVecDim, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Cannot merge PetscLagNodeIndices with different nodeVecDim");
761   ni->nNodes = nNodes = niA->nNodes + niB->nNodes;
762   ni->refct           = 1;
763   PetscCall(PetscMalloc1(nNodes * nodeIdxDim, &ni->nodeIdx));
764   PetscCall(PetscMalloc1(nNodes * nodeVecDim, &ni->nodeVec));
765   PetscCall(PetscArraycpy(ni->nodeIdx, niA->nodeIdx, niA->nNodes * nodeIdxDim));
766   PetscCall(PetscArraycpy(ni->nodeVec, niA->nodeVec, niA->nNodes * nodeVecDim));
767   PetscCall(PetscArraycpy(&ni->nodeIdx[niA->nNodes * nodeIdxDim], niB->nodeIdx, niB->nNodes * nodeIdxDim));
768   PetscCall(PetscArraycpy(&ni->nodeVec[niA->nNodes * nodeVecDim], niB->nodeVec, niB->nNodes * nodeVecDim));
769   *nodeIndices = ni;
770   PetscFunctionReturn(PETSC_SUCCESS);
771 }
772 
773 #define PETSCTUPINTCOMPREVLEX(N) \
774   static int PetscConcat_(PetscTupIntCompRevlex_, N)(const void *a, const void *b) \
775   { \
776     const PetscInt *A = (const PetscInt *)a; \
777     const PetscInt *B = (const PetscInt *)b; \
778     int             i; \
779     PetscInt        diff = 0; \
780     for (i = 0; i < N; i++) { \
781       diff = A[N - i] - B[N - i]; \
782       if (diff) break; \
783     } \
784     return (diff <= 0) ? (diff < 0) ? -1 : 0 : 1; \
785   }
786 
787 PETSCTUPINTCOMPREVLEX(3)
788 PETSCTUPINTCOMPREVLEX(4)
789 PETSCTUPINTCOMPREVLEX(5)
790 PETSCTUPINTCOMPREVLEX(6)
791 PETSCTUPINTCOMPREVLEX(7)
792 
793 static int PetscTupIntCompRevlex_N(const void *a, const void *b)
794 {
795   const PetscInt *A = (const PetscInt *)a;
796   const PetscInt *B = (const PetscInt *)b;
797   PetscInt        i;
798   PetscInt        N    = A[0];
799   PetscInt        diff = 0;
800   for (i = 0; i < N; i++) {
801     diff = A[N - i] - B[N - i];
802     if (diff) break;
803   }
804   return (diff <= 0) ? (diff < 0) ? -1 : 0 : 1;
805 }
806 
807 /* The nodes are not necessarily in revlex order wrt nodeIdx: get the permutation
808  * that puts them in that order */
809 static PetscErrorCode PetscLagNodeIndicesGetPermutation(PetscLagNodeIndices ni, PetscInt *perm[])
810 {
811   PetscFunctionBegin;
812   if (!ni->perm) {
813     PetscInt *sorter;
814     PetscInt  m          = ni->nNodes;
815     PetscInt  nodeIdxDim = ni->nodeIdxDim;
816     PetscInt  i, j, k, l;
817     PetscInt *prm;
818     int (*comp)(const void *, const void *);
819 
820     PetscCall(PetscMalloc1((nodeIdxDim + 2) * m, &sorter));
821     for (k = 0, l = 0, i = 0; i < m; i++) {
822       sorter[k++] = nodeIdxDim + 1;
823       sorter[k++] = i;
824       for (j = 0; j < nodeIdxDim; j++) sorter[k++] = ni->nodeIdx[l++];
825     }
826     switch (nodeIdxDim) {
827     case 2:
828       comp = PetscTupIntCompRevlex_3;
829       break;
830     case 3:
831       comp = PetscTupIntCompRevlex_4;
832       break;
833     case 4:
834       comp = PetscTupIntCompRevlex_5;
835       break;
836     case 5:
837       comp = PetscTupIntCompRevlex_6;
838       break;
839     case 6:
840       comp = PetscTupIntCompRevlex_7;
841       break;
842     default:
843       comp = PetscTupIntCompRevlex_N;
844       break;
845     }
846     qsort(sorter, m, (nodeIdxDim + 2) * sizeof(PetscInt), comp);
847     PetscCall(PetscMalloc1(m, &prm));
848     for (i = 0; i < m; i++) prm[i] = sorter[(nodeIdxDim + 2) * i + 1];
849     ni->perm = prm;
850     PetscCall(PetscFree(sorter));
851   }
852   *perm = ni->perm;
853   PetscFunctionReturn(PETSC_SUCCESS);
854 }
855 
856 static PetscErrorCode PetscDualSpaceDestroy_Lagrange(PetscDualSpace sp)
857 {
858   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
859 
860   PetscFunctionBegin;
861   if (lag->symperms) {
862     PetscInt **selfSyms = lag->symperms[0];
863 
864     if (selfSyms) {
865       PetscInt i, **allocated = &selfSyms[-lag->selfSymOff];
866 
867       for (i = 0; i < lag->numSelfSym; i++) PetscCall(PetscFree(allocated[i]));
868       PetscCall(PetscFree(allocated));
869     }
870     PetscCall(PetscFree(lag->symperms));
871   }
872   if (lag->symflips) {
873     PetscScalar **selfSyms = lag->symflips[0];
874 
875     if (selfSyms) {
876       PetscInt      i;
877       PetscScalar **allocated = &selfSyms[-lag->selfSymOff];
878 
879       for (i = 0; i < lag->numSelfSym; i++) PetscCall(PetscFree(allocated[i]));
880       PetscCall(PetscFree(allocated));
881     }
882     PetscCall(PetscFree(lag->symflips));
883   }
884   PetscCall(Petsc1DNodeFamilyDestroy(&lag->nodeFamily));
885   PetscCall(PetscLagNodeIndicesDestroy(&lag->vertIndices));
886   PetscCall(PetscLagNodeIndicesDestroy(&lag->intNodeIndices));
887   PetscCall(PetscLagNodeIndicesDestroy(&lag->allNodeIndices));
888   PetscCall(PetscFree(lag));
889   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetContinuity_C", NULL));
890   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetContinuity_C", NULL));
891   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetTensor_C", NULL));
892   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetTensor_C", NULL));
893   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetTrimmed_C", NULL));
894   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetTrimmed_C", NULL));
895   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetNodeType_C", NULL));
896   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetNodeType_C", NULL));
897   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetUseMoments_C", NULL));
898   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetUseMoments_C", NULL));
899   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetMomentOrder_C", NULL));
900   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetMomentOrder_C", NULL));
901   PetscFunctionReturn(PETSC_SUCCESS);
902 }
903 
904 static PetscErrorCode PetscDualSpaceLagrangeView_Ascii(PetscDualSpace sp, PetscViewer viewer)
905 {
906   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
907 
908   PetscFunctionBegin;
909   PetscCall(PetscViewerASCIIPrintf(viewer, "%s %s%sLagrange dual space\n", lag->continuous ? "Continuous" : "Discontinuous", lag->tensorSpace ? "tensor " : "", lag->trimmed ? "trimmed " : ""));
910   PetscFunctionReturn(PETSC_SUCCESS);
911 }
912 
913 static PetscErrorCode PetscDualSpaceView_Lagrange(PetscDualSpace sp, PetscViewer viewer)
914 {
915   PetscBool iascii;
916 
917   PetscFunctionBegin;
918   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
919   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 2);
920   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
921   if (iascii) PetscCall(PetscDualSpaceLagrangeView_Ascii(sp, viewer));
922   PetscFunctionReturn(PETSC_SUCCESS);
923 }
924 
925 static PetscErrorCode PetscDualSpaceSetFromOptions_Lagrange(PetscDualSpace sp, PetscOptionItems *PetscOptionsObject)
926 {
927   PetscBool       continuous, tensor, trimmed, flg, flg2, flg3;
928   PetscDTNodeType nodeType;
929   PetscReal       nodeExponent;
930   PetscInt        momentOrder;
931   PetscBool       nodeEndpoints, useMoments;
932 
933   PetscFunctionBegin;
934   PetscCall(PetscDualSpaceLagrangeGetContinuity(sp, &continuous));
935   PetscCall(PetscDualSpaceLagrangeGetTensor(sp, &tensor));
936   PetscCall(PetscDualSpaceLagrangeGetTrimmed(sp, &trimmed));
937   PetscCall(PetscDualSpaceLagrangeGetNodeType(sp, &nodeType, &nodeEndpoints, &nodeExponent));
938   if (nodeType == PETSCDTNODES_DEFAULT) nodeType = PETSCDTNODES_GAUSSJACOBI;
939   PetscCall(PetscDualSpaceLagrangeGetUseMoments(sp, &useMoments));
940   PetscCall(PetscDualSpaceLagrangeGetMomentOrder(sp, &momentOrder));
941   PetscOptionsHeadBegin(PetscOptionsObject, "PetscDualSpace Lagrange Options");
942   PetscCall(PetscOptionsBool("-petscdualspace_lagrange_continuity", "Flag for continuous element", "PetscDualSpaceLagrangeSetContinuity", continuous, &continuous, &flg));
943   if (flg) PetscCall(PetscDualSpaceLagrangeSetContinuity(sp, continuous));
944   PetscCall(PetscOptionsBool("-petscdualspace_lagrange_tensor", "Flag for tensor dual space", "PetscDualSpaceLagrangeSetTensor", tensor, &tensor, &flg));
945   if (flg) PetscCall(PetscDualSpaceLagrangeSetTensor(sp, tensor));
946   PetscCall(PetscOptionsBool("-petscdualspace_lagrange_trimmed", "Flag for trimmed dual space", "PetscDualSpaceLagrangeSetTrimmed", trimmed, &trimmed, &flg));
947   if (flg) PetscCall(PetscDualSpaceLagrangeSetTrimmed(sp, trimmed));
948   PetscCall(PetscOptionsEnum("-petscdualspace_lagrange_node_type", "Lagrange node location type", "PetscDualSpaceLagrangeSetNodeType", PetscDTNodeTypes, (PetscEnum)nodeType, (PetscEnum *)&nodeType, &flg));
949   PetscCall(PetscOptionsBool("-petscdualspace_lagrange_node_endpoints", "Flag for nodes that include endpoints", "PetscDualSpaceLagrangeSetNodeType", nodeEndpoints, &nodeEndpoints, &flg2));
950   flg3 = PETSC_FALSE;
951   if (nodeType == PETSCDTNODES_GAUSSJACOBI) PetscCall(PetscOptionsReal("-petscdualspace_lagrange_node_exponent", "Gauss-Jacobi weight function exponent", "PetscDualSpaceLagrangeSetNodeType", nodeExponent, &nodeExponent, &flg3));
952   if (flg || flg2 || flg3) PetscCall(PetscDualSpaceLagrangeSetNodeType(sp, nodeType, nodeEndpoints, nodeExponent));
953   PetscCall(PetscOptionsBool("-petscdualspace_lagrange_use_moments", "Use moments (where appropriate) for functionals", "PetscDualSpaceLagrangeSetUseMoments", useMoments, &useMoments, &flg));
954   if (flg) PetscCall(PetscDualSpaceLagrangeSetUseMoments(sp, useMoments));
955   PetscCall(PetscOptionsInt("-petscdualspace_lagrange_moment_order", "Quadrature order for moment functionals", "PetscDualSpaceLagrangeSetMomentOrder", momentOrder, &momentOrder, &flg));
956   if (flg) PetscCall(PetscDualSpaceLagrangeSetMomentOrder(sp, momentOrder));
957   PetscOptionsHeadEnd();
958   PetscFunctionReturn(PETSC_SUCCESS);
959 }
960 
961 static PetscErrorCode PetscDualSpaceDuplicate_Lagrange(PetscDualSpace sp, PetscDualSpace spNew)
962 {
963   PetscBool           cont, tensor, trimmed, boundary;
964   PetscDTNodeType     nodeType;
965   PetscReal           exponent;
966   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
967 
968   PetscFunctionBegin;
969   PetscCall(PetscDualSpaceLagrangeGetContinuity(sp, &cont));
970   PetscCall(PetscDualSpaceLagrangeSetContinuity(spNew, cont));
971   PetscCall(PetscDualSpaceLagrangeGetTensor(sp, &tensor));
972   PetscCall(PetscDualSpaceLagrangeSetTensor(spNew, tensor));
973   PetscCall(PetscDualSpaceLagrangeGetTrimmed(sp, &trimmed));
974   PetscCall(PetscDualSpaceLagrangeSetTrimmed(spNew, trimmed));
975   PetscCall(PetscDualSpaceLagrangeGetNodeType(sp, &nodeType, &boundary, &exponent));
976   PetscCall(PetscDualSpaceLagrangeSetNodeType(spNew, nodeType, boundary, exponent));
977   if (lag->nodeFamily) {
978     PetscDualSpace_Lag *lagnew = (PetscDualSpace_Lag *)spNew->data;
979 
980     PetscCall(Petsc1DNodeFamilyReference(lag->nodeFamily));
981     lagnew->nodeFamily = lag->nodeFamily;
982   }
983   PetscFunctionReturn(PETSC_SUCCESS);
984 }
985 
986 /* for making tensor product spaces: take a dual space and product a segment space that has all the same
987  * specifications (trimmed, continuous, order, node set), except for the form degree */
988 static PetscErrorCode PetscDualSpaceCreateEdgeSubspace_Lagrange(PetscDualSpace sp, PetscInt order, PetscInt k, PetscInt Nc, PetscBool interiorOnly, PetscDualSpace *bdsp)
989 {
990   DM                  K;
991   PetscDualSpace_Lag *newlag;
992 
993   PetscFunctionBegin;
994   PetscCall(PetscDualSpaceDuplicate(sp, bdsp));
995   PetscCall(PetscDualSpaceSetFormDegree(*bdsp, k));
996   PetscCall(DMPlexCreateReferenceCell(PETSC_COMM_SELF, DMPolytopeTypeSimpleShape(1, PETSC_TRUE), &K));
997   PetscCall(PetscDualSpaceSetDM(*bdsp, K));
998   PetscCall(DMDestroy(&K));
999   PetscCall(PetscDualSpaceSetOrder(*bdsp, order));
1000   PetscCall(PetscDualSpaceSetNumComponents(*bdsp, Nc));
1001   newlag               = (PetscDualSpace_Lag *)(*bdsp)->data;
1002   newlag->interiorOnly = interiorOnly;
1003   PetscCall(PetscDualSpaceSetUp(*bdsp));
1004   PetscFunctionReturn(PETSC_SUCCESS);
1005 }
1006 
1007 /* just the points, weights aren't handled */
1008 static PetscErrorCode PetscQuadratureCreateTensor(PetscQuadrature trace, PetscQuadrature fiber, PetscQuadrature *product)
1009 {
1010   PetscInt         dimTrace, dimFiber;
1011   PetscInt         numPointsTrace, numPointsFiber;
1012   PetscInt         dim, numPoints;
1013   const PetscReal *pointsTrace;
1014   const PetscReal *pointsFiber;
1015   PetscReal       *points;
1016   PetscInt         i, j, k, p;
1017 
1018   PetscFunctionBegin;
1019   PetscCall(PetscQuadratureGetData(trace, &dimTrace, NULL, &numPointsTrace, &pointsTrace, NULL));
1020   PetscCall(PetscQuadratureGetData(fiber, &dimFiber, NULL, &numPointsFiber, &pointsFiber, NULL));
1021   dim       = dimTrace + dimFiber;
1022   numPoints = numPointsFiber * numPointsTrace;
1023   PetscCall(PetscMalloc1(numPoints * dim, &points));
1024   for (p = 0, j = 0; j < numPointsFiber; j++) {
1025     for (i = 0; i < numPointsTrace; i++, p++) {
1026       for (k = 0; k < dimTrace; k++) points[p * dim + k] = pointsTrace[i * dimTrace + k];
1027       for (k = 0; k < dimFiber; k++) points[p * dim + dimTrace + k] = pointsFiber[j * dimFiber + k];
1028     }
1029   }
1030   PetscCall(PetscQuadratureCreate(PETSC_COMM_SELF, product));
1031   PetscCall(PetscQuadratureSetData(*product, dim, 0, numPoints, points, NULL));
1032   PetscFunctionReturn(PETSC_SUCCESS);
1033 }
1034 
1035 /* Kronecker tensor product where matrix is considered a matrix of k-forms, so that
1036  * the entries in the product matrix are wedge products of the entries in the original matrices */
1037 static PetscErrorCode MatTensorAltV(Mat trace, Mat fiber, PetscInt dimTrace, PetscInt kTrace, PetscInt dimFiber, PetscInt kFiber, Mat *product)
1038 {
1039   PetscInt     mTrace, nTrace, mFiber, nFiber, m, n, k, i, j, l;
1040   PetscInt     dim, NkTrace, NkFiber, Nk;
1041   PetscInt     dT, dF;
1042   PetscInt    *nnzTrace, *nnzFiber, *nnz;
1043   PetscInt     iT, iF, jT, jF, il, jl;
1044   PetscReal   *workT, *workT2, *workF, *workF2, *work, *workstar;
1045   PetscReal   *projT, *projF;
1046   PetscReal   *projTstar, *projFstar;
1047   PetscReal   *wedgeMat;
1048   PetscReal    sign;
1049   PetscScalar *workS;
1050   Mat          prod;
1051   /* this produces dof groups that look like the identity */
1052 
1053   PetscFunctionBegin;
1054   PetscCall(MatGetSize(trace, &mTrace, &nTrace));
1055   PetscCall(PetscDTBinomialInt(dimTrace, PetscAbsInt(kTrace), &NkTrace));
1056   PetscCheck(nTrace % NkTrace == 0, PETSC_COMM_SELF, PETSC_ERR_PLIB, "point value space of trace matrix is not a multiple of k-form size");
1057   PetscCall(MatGetSize(fiber, &mFiber, &nFiber));
1058   PetscCall(PetscDTBinomialInt(dimFiber, PetscAbsInt(kFiber), &NkFiber));
1059   PetscCheck(nFiber % NkFiber == 0, PETSC_COMM_SELF, PETSC_ERR_PLIB, "point value space of fiber matrix is not a multiple of k-form size");
1060   PetscCall(PetscMalloc2(mTrace, &nnzTrace, mFiber, &nnzFiber));
1061   for (i = 0; i < mTrace; i++) {
1062     PetscCall(MatGetRow(trace, i, &nnzTrace[i], NULL, NULL));
1063     PetscCheck(nnzTrace[i] % NkTrace == 0, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nonzeros in trace matrix are not in k-form size blocks");
1064   }
1065   for (i = 0; i < mFiber; i++) {
1066     PetscCall(MatGetRow(fiber, i, &nnzFiber[i], NULL, NULL));
1067     PetscCheck(nnzFiber[i] % NkFiber == 0, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nonzeros in fiber matrix are not in k-form size blocks");
1068   }
1069   dim = dimTrace + dimFiber;
1070   k   = kFiber + kTrace;
1071   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(k), &Nk));
1072   m = mTrace * mFiber;
1073   PetscCall(PetscMalloc1(m, &nnz));
1074   for (l = 0, j = 0; j < mFiber; j++)
1075     for (i = 0; i < mTrace; i++, l++) nnz[l] = (nnzTrace[i] / NkTrace) * (nnzFiber[j] / NkFiber) * Nk;
1076   n = (nTrace / NkTrace) * (nFiber / NkFiber) * Nk;
1077   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, m, n, 0, nnz, &prod));
1078   PetscCall(PetscObjectSetOptionsPrefix((PetscObject)prod, "altv_"));
1079   PetscCall(PetscFree(nnz));
1080   PetscCall(PetscFree2(nnzTrace, nnzFiber));
1081   /* reasoning about which points each dof needs depends on having zeros computed at points preserved */
1082   PetscCall(MatSetOption(prod, MAT_IGNORE_ZERO_ENTRIES, PETSC_FALSE));
1083   /* compute pullbacks */
1084   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(kTrace), &dT));
1085   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(kFiber), &dF));
1086   PetscCall(PetscMalloc4(dimTrace * dim, &projT, dimFiber * dim, &projF, dT * NkTrace, &projTstar, dF * NkFiber, &projFstar));
1087   PetscCall(PetscArrayzero(projT, dimTrace * dim));
1088   for (i = 0; i < dimTrace; i++) projT[i * (dim + 1)] = 1.;
1089   PetscCall(PetscArrayzero(projF, dimFiber * dim));
1090   for (i = 0; i < dimFiber; i++) projF[i * (dim + 1) + dimTrace] = 1.;
1091   PetscCall(PetscDTAltVPullbackMatrix(dim, dimTrace, projT, kTrace, projTstar));
1092   PetscCall(PetscDTAltVPullbackMatrix(dim, dimFiber, projF, kFiber, projFstar));
1093   PetscCall(PetscMalloc5(dT, &workT, dF, &workF, Nk, &work, Nk, &workstar, Nk, &workS));
1094   PetscCall(PetscMalloc2(dT, &workT2, dF, &workF2));
1095   PetscCall(PetscMalloc1(Nk * dT, &wedgeMat));
1096   sign = (PetscAbsInt(kTrace * kFiber) & 1) ? -1. : 1.;
1097   for (i = 0, iF = 0; iF < mFiber; iF++) {
1098     PetscInt           ncolsF, nformsF;
1099     const PetscInt    *colsF;
1100     const PetscScalar *valsF;
1101 
1102     PetscCall(MatGetRow(fiber, iF, &ncolsF, &colsF, &valsF));
1103     nformsF = ncolsF / NkFiber;
1104     for (iT = 0; iT < mTrace; iT++, i++) {
1105       PetscInt           ncolsT, nformsT;
1106       const PetscInt    *colsT;
1107       const PetscScalar *valsT;
1108 
1109       PetscCall(MatGetRow(trace, iT, &ncolsT, &colsT, &valsT));
1110       nformsT = ncolsT / NkTrace;
1111       for (j = 0, jF = 0; jF < nformsF; jF++) {
1112         PetscInt colF = colsF[jF * NkFiber] / NkFiber;
1113 
1114         for (il = 0; il < dF; il++) {
1115           PetscReal val = 0.;
1116           for (jl = 0; jl < NkFiber; jl++) val += projFstar[il * NkFiber + jl] * PetscRealPart(valsF[jF * NkFiber + jl]);
1117           workF[il] = val;
1118         }
1119         if (kFiber < 0) {
1120           for (il = 0; il < dF; il++) workF2[il] = workF[il];
1121           PetscCall(PetscDTAltVStar(dim, PetscAbsInt(kFiber), 1, workF2, workF));
1122         }
1123         PetscCall(PetscDTAltVWedgeMatrix(dim, PetscAbsInt(kFiber), PetscAbsInt(kTrace), workF, wedgeMat));
1124         for (jT = 0; jT < nformsT; jT++, j++) {
1125           PetscInt           colT = colsT[jT * NkTrace] / NkTrace;
1126           PetscInt           col  = colF * (nTrace / NkTrace) + colT;
1127           const PetscScalar *vals;
1128 
1129           for (il = 0; il < dT; il++) {
1130             PetscReal val = 0.;
1131             for (jl = 0; jl < NkTrace; jl++) val += projTstar[il * NkTrace + jl] * PetscRealPart(valsT[jT * NkTrace + jl]);
1132             workT[il] = val;
1133           }
1134           if (kTrace < 0) {
1135             for (il = 0; il < dT; il++) workT2[il] = workT[il];
1136             PetscCall(PetscDTAltVStar(dim, PetscAbsInt(kTrace), 1, workT2, workT));
1137           }
1138 
1139           for (il = 0; il < Nk; il++) {
1140             PetscReal val = 0.;
1141             for (jl = 0; jl < dT; jl++) val += sign * wedgeMat[il * dT + jl] * workT[jl];
1142             work[il] = val;
1143           }
1144           if (k < 0) {
1145             PetscCall(PetscDTAltVStar(dim, PetscAbsInt(k), -1, work, workstar));
1146 #if defined(PETSC_USE_COMPLEX)
1147             for (l = 0; l < Nk; l++) workS[l] = workstar[l];
1148             vals = &workS[0];
1149 #else
1150             vals = &workstar[0];
1151 #endif
1152           } else {
1153 #if defined(PETSC_USE_COMPLEX)
1154             for (l = 0; l < Nk; l++) workS[l] = work[l];
1155             vals = &workS[0];
1156 #else
1157             vals = &work[0];
1158 #endif
1159           }
1160           for (l = 0; l < Nk; l++) PetscCall(MatSetValue(prod, i, col * Nk + l, vals[l], INSERT_VALUES)); /* Nk */
1161         } /* jT */
1162       } /* jF */
1163       PetscCall(MatRestoreRow(trace, iT, &ncolsT, &colsT, &valsT));
1164     } /* iT */
1165     PetscCall(MatRestoreRow(fiber, iF, &ncolsF, &colsF, &valsF));
1166   } /* iF */
1167   PetscCall(PetscFree(wedgeMat));
1168   PetscCall(PetscFree4(projT, projF, projTstar, projFstar));
1169   PetscCall(PetscFree2(workT2, workF2));
1170   PetscCall(PetscFree5(workT, workF, work, workstar, workS));
1171   PetscCall(MatAssemblyBegin(prod, MAT_FINAL_ASSEMBLY));
1172   PetscCall(MatAssemblyEnd(prod, MAT_FINAL_ASSEMBLY));
1173   *product = prod;
1174   PetscFunctionReturn(PETSC_SUCCESS);
1175 }
1176 
1177 /* Union of quadrature points, with an attempt to identify common points in the two sets */
1178 static PetscErrorCode PetscQuadraturePointsMerge(PetscQuadrature quadA, PetscQuadrature quadB, PetscQuadrature *quadJoint, PetscInt *aToJoint[], PetscInt *bToJoint[])
1179 {
1180   PetscInt         dimA, dimB;
1181   PetscInt         nA, nB, nJoint, i, j, d;
1182   const PetscReal *pointsA;
1183   const PetscReal *pointsB;
1184   PetscReal       *pointsJoint;
1185   PetscInt        *aToJ, *bToJ;
1186   PetscQuadrature  qJ;
1187 
1188   PetscFunctionBegin;
1189   PetscCall(PetscQuadratureGetData(quadA, &dimA, NULL, &nA, &pointsA, NULL));
1190   PetscCall(PetscQuadratureGetData(quadB, &dimB, NULL, &nB, &pointsB, NULL));
1191   PetscCheck(dimA == dimB, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Quadrature points must be in the same dimension");
1192   nJoint = nA;
1193   PetscCall(PetscMalloc1(nA, &aToJ));
1194   for (i = 0; i < nA; i++) aToJ[i] = i;
1195   PetscCall(PetscMalloc1(nB, &bToJ));
1196   for (i = 0; i < nB; i++) {
1197     for (j = 0; j < nA; j++) {
1198       bToJ[i] = -1;
1199       for (d = 0; d < dimA; d++)
1200         if (PetscAbsReal(pointsB[i * dimA + d] - pointsA[j * dimA + d]) > PETSC_SMALL) break;
1201       if (d == dimA) {
1202         bToJ[i] = j;
1203         break;
1204       }
1205     }
1206     if (bToJ[i] == -1) bToJ[i] = nJoint++;
1207   }
1208   *aToJoint = aToJ;
1209   *bToJoint = bToJ;
1210   PetscCall(PetscMalloc1(nJoint * dimA, &pointsJoint));
1211   PetscCall(PetscArraycpy(pointsJoint, pointsA, nA * dimA));
1212   for (i = 0; i < nB; i++) {
1213     if (bToJ[i] >= nA) {
1214       for (d = 0; d < dimA; d++) pointsJoint[bToJ[i] * dimA + d] = pointsB[i * dimA + d];
1215     }
1216   }
1217   PetscCall(PetscQuadratureCreate(PETSC_COMM_SELF, &qJ));
1218   PetscCall(PetscQuadratureSetData(qJ, dimA, 0, nJoint, pointsJoint, NULL));
1219   *quadJoint = qJ;
1220   PetscFunctionReturn(PETSC_SUCCESS);
1221 }
1222 
1223 /* Matrices matA and matB are both quadrature -> dof matrices: produce a matrix that is joint quadrature -> union of
1224  * dofs, where the joint quadrature was produced by PetscQuadraturePointsMerge */
1225 static PetscErrorCode MatricesMerge(Mat matA, Mat matB, PetscInt dim, PetscInt k, PetscInt numMerged, const PetscInt aToMerged[], const PetscInt bToMerged[], Mat *matMerged)
1226 {
1227   PetscInt  m, n, mA, nA, mB, nB, Nk, i, j, l;
1228   Mat       M;
1229   PetscInt *nnz;
1230   PetscInt  maxnnz;
1231   PetscInt *work;
1232 
1233   PetscFunctionBegin;
1234   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(k), &Nk));
1235   PetscCall(MatGetSize(matA, &mA, &nA));
1236   PetscCheck(nA % Nk == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "matA column space not a multiple of k-form size");
1237   PetscCall(MatGetSize(matB, &mB, &nB));
1238   PetscCheck(nB % Nk == 0, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "matB column space not a multiple of k-form size");
1239   m = mA + mB;
1240   n = numMerged * Nk;
1241   PetscCall(PetscMalloc1(m, &nnz));
1242   maxnnz = 0;
1243   for (i = 0; i < mA; i++) {
1244     PetscCall(MatGetRow(matA, i, &nnz[i], NULL, NULL));
1245     PetscCheck(nnz[i] % Nk == 0, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nonzeros in matA are not in k-form size blocks");
1246     maxnnz = PetscMax(maxnnz, nnz[i]);
1247   }
1248   for (i = 0; i < mB; i++) {
1249     PetscCall(MatGetRow(matB, i, &nnz[i + mA], NULL, NULL));
1250     PetscCheck(nnz[i + mA] % Nk == 0, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nonzeros in matB are not in k-form size blocks");
1251     maxnnz = PetscMax(maxnnz, nnz[i + mA]);
1252   }
1253   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, m, n, 0, nnz, &M));
1254   PetscCall(PetscObjectSetOptionsPrefix((PetscObject)M, "altv_"));
1255   PetscCall(PetscFree(nnz));
1256   /* reasoning about which points each dof needs depends on having zeros computed at points preserved */
1257   PetscCall(MatSetOption(M, MAT_IGNORE_ZERO_ENTRIES, PETSC_FALSE));
1258   PetscCall(PetscMalloc1(maxnnz, &work));
1259   for (i = 0; i < mA; i++) {
1260     const PetscInt    *cols;
1261     const PetscScalar *vals;
1262     PetscInt           nCols;
1263     PetscCall(MatGetRow(matA, i, &nCols, &cols, &vals));
1264     for (j = 0; j < nCols / Nk; j++) {
1265       PetscInt newCol = aToMerged[cols[j * Nk] / Nk];
1266       for (l = 0; l < Nk; l++) work[j * Nk + l] = newCol * Nk + l;
1267     }
1268     PetscCall(MatSetValuesBlocked(M, 1, &i, nCols, work, vals, INSERT_VALUES));
1269     PetscCall(MatRestoreRow(matA, i, &nCols, &cols, &vals));
1270   }
1271   for (i = 0; i < mB; i++) {
1272     const PetscInt    *cols;
1273     const PetscScalar *vals;
1274 
1275     PetscInt row = i + mA;
1276     PetscInt nCols;
1277     PetscCall(MatGetRow(matB, i, &nCols, &cols, &vals));
1278     for (j = 0; j < nCols / Nk; j++) {
1279       PetscInt newCol = bToMerged[cols[j * Nk] / Nk];
1280       for (l = 0; l < Nk; l++) work[j * Nk + l] = newCol * Nk + l;
1281     }
1282     PetscCall(MatSetValuesBlocked(M, 1, &row, nCols, work, vals, INSERT_VALUES));
1283     PetscCall(MatRestoreRow(matB, i, &nCols, &cols, &vals));
1284   }
1285   PetscCall(PetscFree(work));
1286   PetscCall(MatAssemblyBegin(M, MAT_FINAL_ASSEMBLY));
1287   PetscCall(MatAssemblyEnd(M, MAT_FINAL_ASSEMBLY));
1288   *matMerged = M;
1289   PetscFunctionReturn(PETSC_SUCCESS);
1290 }
1291 
1292 /* Take a dual space and product a segment space that has all the same specifications (trimmed, continuous, order,
1293  * node set), except for the form degree.  For computing boundary dofs and for making tensor product spaces */
1294 static PetscErrorCode PetscDualSpaceCreateFacetSubspace_Lagrange(PetscDualSpace sp, DM K, PetscInt f, PetscInt k, PetscInt Ncopies, PetscBool interiorOnly, PetscDualSpace *bdsp)
1295 {
1296   PetscInt            Nknew, Ncnew;
1297   PetscInt            dim, pointDim = -1;
1298   PetscInt            depth;
1299   DM                  dm;
1300   PetscDualSpace_Lag *newlag;
1301 
1302   PetscFunctionBegin;
1303   PetscCall(PetscDualSpaceGetDM(sp, &dm));
1304   PetscCall(DMGetDimension(dm, &dim));
1305   PetscCall(DMPlexGetDepth(dm, &depth));
1306   PetscCall(PetscDualSpaceDuplicate(sp, bdsp));
1307   PetscCall(PetscDualSpaceSetFormDegree(*bdsp, k));
1308   if (!K) {
1309     if (depth == dim) {
1310       DMPolytopeType ct;
1311 
1312       pointDim = dim - 1;
1313       PetscCall(DMPlexGetCellType(dm, f, &ct));
1314       PetscCall(DMPlexCreateReferenceCell(PETSC_COMM_SELF, ct, &K));
1315     } else if (depth == 1) {
1316       pointDim = 0;
1317       PetscCall(DMPlexCreateReferenceCell(PETSC_COMM_SELF, DM_POLYTOPE_POINT, &K));
1318     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_PLIB, "Unsupported interpolation state of reference element");
1319   } else {
1320     PetscCall(PetscObjectReference((PetscObject)K));
1321     PetscCall(DMGetDimension(K, &pointDim));
1322   }
1323   PetscCall(PetscDualSpaceSetDM(*bdsp, K));
1324   PetscCall(DMDestroy(&K));
1325   PetscCall(PetscDTBinomialInt(pointDim, PetscAbsInt(k), &Nknew));
1326   Ncnew = Nknew * Ncopies;
1327   PetscCall(PetscDualSpaceSetNumComponents(*bdsp, Ncnew));
1328   newlag               = (PetscDualSpace_Lag *)(*bdsp)->data;
1329   newlag->interiorOnly = interiorOnly;
1330   PetscCall(PetscDualSpaceSetUp(*bdsp));
1331   PetscFunctionReturn(PETSC_SUCCESS);
1332 }
1333 
1334 /* Construct simplex nodes from a nodefamily, add Nk dof vectors of length Nk at each node.
1335  * Return the (quadrature, matrix) form of the dofs and the nodeIndices form as well.
1336  *
1337  * Sometimes we want a set of nodes to be contained in the interior of the element,
1338  * even when the node scheme puts nodes on the boundaries.  numNodeSkip tells
1339  * the routine how many "layers" of nodes need to be skipped.
1340  * */
1341 static PetscErrorCode PetscDualSpaceLagrangeCreateSimplexNodeMat(Petsc1DNodeFamily nodeFamily, PetscInt dim, PetscInt sum, PetscInt Nk, PetscInt numNodeSkip, PetscQuadrature *iNodes, Mat *iMat, PetscLagNodeIndices *nodeIndices)
1342 {
1343   PetscReal          *extraNodeCoords, *nodeCoords;
1344   PetscInt            nNodes, nExtraNodes;
1345   PetscInt            i, j, k, extraSum = sum + numNodeSkip * (1 + dim);
1346   PetscQuadrature     intNodes;
1347   Mat                 intMat;
1348   PetscLagNodeIndices ni;
1349 
1350   PetscFunctionBegin;
1351   PetscCall(PetscDTBinomialInt(dim + sum, dim, &nNodes));
1352   PetscCall(PetscDTBinomialInt(dim + extraSum, dim, &nExtraNodes));
1353 
1354   PetscCall(PetscMalloc1(dim * nExtraNodes, &extraNodeCoords));
1355   PetscCall(PetscNew(&ni));
1356   ni->nodeIdxDim = dim + 1;
1357   ni->nodeVecDim = Nk;
1358   ni->nNodes     = nNodes * Nk;
1359   ni->refct      = 1;
1360   PetscCall(PetscMalloc1(nNodes * Nk * (dim + 1), &ni->nodeIdx));
1361   PetscCall(PetscMalloc1(nNodes * Nk * Nk, &ni->nodeVec));
1362   for (i = 0; i < nNodes; i++)
1363     for (j = 0; j < Nk; j++)
1364       for (k = 0; k < Nk; k++) ni->nodeVec[(i * Nk + j) * Nk + k] = (j == k) ? 1. : 0.;
1365   PetscCall(Petsc1DNodeFamilyComputeSimplexNodes(nodeFamily, dim, extraSum, extraNodeCoords));
1366   if (numNodeSkip) {
1367     PetscInt  k;
1368     PetscInt *tup;
1369 
1370     PetscCall(PetscMalloc1(dim * nNodes, &nodeCoords));
1371     PetscCall(PetscMalloc1(dim + 1, &tup));
1372     for (k = 0; k < nNodes; k++) {
1373       PetscInt j, c;
1374       PetscInt index;
1375 
1376       PetscCall(PetscDTIndexToBary(dim + 1, sum, k, tup));
1377       for (j = 0; j < dim + 1; j++) tup[j] += numNodeSkip;
1378       for (c = 0; c < Nk; c++) {
1379         for (j = 0; j < dim + 1; j++) ni->nodeIdx[(k * Nk + c) * (dim + 1) + j] = tup[j] + 1;
1380       }
1381       PetscCall(PetscDTBaryToIndex(dim + 1, extraSum, tup, &index));
1382       for (j = 0; j < dim; j++) nodeCoords[k * dim + j] = extraNodeCoords[index * dim + j];
1383     }
1384     PetscCall(PetscFree(tup));
1385     PetscCall(PetscFree(extraNodeCoords));
1386   } else {
1387     PetscInt  k;
1388     PetscInt *tup;
1389 
1390     nodeCoords = extraNodeCoords;
1391     PetscCall(PetscMalloc1(dim + 1, &tup));
1392     for (k = 0; k < nNodes; k++) {
1393       PetscInt j, c;
1394 
1395       PetscCall(PetscDTIndexToBary(dim + 1, sum, k, tup));
1396       for (c = 0; c < Nk; c++) {
1397         for (j = 0; j < dim + 1; j++) {
1398           /* barycentric indices can have zeros, but we don't want to push forward zeros because it makes it harder to
1399            * determine which nodes correspond to which under symmetries, so we increase by 1.  This is fine
1400            * because the nodeIdx coordinates don't have any meaning other than helping to identify symmetries */
1401           ni->nodeIdx[(k * Nk + c) * (dim + 1) + j] = tup[j] + 1;
1402         }
1403       }
1404     }
1405     PetscCall(PetscFree(tup));
1406   }
1407   PetscCall(PetscQuadratureCreate(PETSC_COMM_SELF, &intNodes));
1408   PetscCall(PetscQuadratureSetData(intNodes, dim, 0, nNodes, nodeCoords, NULL));
1409   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, nNodes * Nk, nNodes * Nk, Nk, NULL, &intMat));
1410   PetscCall(PetscObjectSetOptionsPrefix((PetscObject)intMat, "lag_"));
1411   PetscCall(MatSetOption(intMat, MAT_IGNORE_ZERO_ENTRIES, PETSC_FALSE));
1412   for (j = 0; j < nNodes * Nk; j++) {
1413     PetscInt rem = j % Nk;
1414     PetscInt a, aprev = j - rem;
1415     PetscInt anext = aprev + Nk;
1416 
1417     for (a = aprev; a < anext; a++) PetscCall(MatSetValue(intMat, j, a, (a == j) ? 1. : 0., INSERT_VALUES));
1418   }
1419   PetscCall(MatAssemblyBegin(intMat, MAT_FINAL_ASSEMBLY));
1420   PetscCall(MatAssemblyEnd(intMat, MAT_FINAL_ASSEMBLY));
1421   *iNodes      = intNodes;
1422   *iMat        = intMat;
1423   *nodeIndices = ni;
1424   PetscFunctionReturn(PETSC_SUCCESS);
1425 }
1426 
1427 /* once the nodeIndices have been created for the interior of the reference cell, and for all of the boundary cells,
1428  * push forward the boundary dofs and concatenate them into the full node indices for the dual space */
1429 static PetscErrorCode PetscDualSpaceLagrangeCreateAllNodeIdx(PetscDualSpace sp)
1430 {
1431   DM                  dm;
1432   PetscInt            dim, nDofs;
1433   PetscSection        section;
1434   PetscInt            pStart, pEnd, p;
1435   PetscInt            formDegree, Nk;
1436   PetscInt            nodeIdxDim, spintdim;
1437   PetscDualSpace_Lag *lag;
1438   PetscLagNodeIndices ni, verti;
1439 
1440   PetscFunctionBegin;
1441   lag   = (PetscDualSpace_Lag *)sp->data;
1442   verti = lag->vertIndices;
1443   PetscCall(PetscDualSpaceGetDM(sp, &dm));
1444   PetscCall(DMGetDimension(dm, &dim));
1445   PetscCall(PetscDualSpaceGetFormDegree(sp, &formDegree));
1446   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(formDegree), &Nk));
1447   PetscCall(PetscDualSpaceGetSection(sp, &section));
1448   PetscCall(PetscSectionGetStorageSize(section, &nDofs));
1449   PetscCall(PetscNew(&ni));
1450   ni->nodeIdxDim = nodeIdxDim = verti->nodeIdxDim;
1451   ni->nodeVecDim              = Nk;
1452   ni->nNodes                  = nDofs;
1453   ni->refct                   = 1;
1454   PetscCall(PetscMalloc1(nodeIdxDim * nDofs, &ni->nodeIdx));
1455   PetscCall(PetscMalloc1(Nk * nDofs, &ni->nodeVec));
1456   PetscCall(DMPlexGetChart(dm, &pStart, &pEnd));
1457   PetscCall(PetscSectionGetDof(section, 0, &spintdim));
1458   if (spintdim) {
1459     PetscCall(PetscArraycpy(ni->nodeIdx, lag->intNodeIndices->nodeIdx, spintdim * nodeIdxDim));
1460     PetscCall(PetscArraycpy(ni->nodeVec, lag->intNodeIndices->nodeVec, spintdim * Nk));
1461   }
1462   for (p = pStart + 1; p < pEnd; p++) {
1463     PetscDualSpace      psp = sp->pointSpaces[p];
1464     PetscDualSpace_Lag *plag;
1465     PetscInt            dof, off;
1466 
1467     PetscCall(PetscSectionGetDof(section, p, &dof));
1468     if (!dof) continue;
1469     plag = (PetscDualSpace_Lag *)psp->data;
1470     PetscCall(PetscSectionGetOffset(section, p, &off));
1471     PetscCall(PetscLagNodeIndicesPushForward(dm, verti, p, plag->vertIndices, plag->intNodeIndices, 0, formDegree, &ni->nodeIdx[off * nodeIdxDim], &ni->nodeVec[off * Nk]));
1472   }
1473   lag->allNodeIndices = ni;
1474   PetscFunctionReturn(PETSC_SUCCESS);
1475 }
1476 
1477 /* once the (quadrature, Matrix) forms of the dofs have been created for the interior of the
1478  * reference cell and for the boundary cells, jk
1479  * push forward the boundary data and concatenate them into the full (quadrature, matrix) data
1480  * for the dual space */
1481 static PetscErrorCode PetscDualSpaceCreateAllDataFromInteriorData(PetscDualSpace sp)
1482 {
1483   DM              dm;
1484   PetscSection    section;
1485   PetscInt        pStart, pEnd, p, k, Nk, dim, Nc;
1486   PetscInt        nNodes;
1487   PetscInt        countNodes;
1488   Mat             allMat;
1489   PetscQuadrature allNodes;
1490   PetscInt        nDofs;
1491   PetscInt        maxNzforms, j;
1492   PetscScalar    *work;
1493   PetscReal      *L, *J, *Jinv, *v0, *pv0;
1494   PetscInt       *iwork;
1495   PetscReal      *nodes;
1496 
1497   PetscFunctionBegin;
1498   PetscCall(PetscDualSpaceGetDM(sp, &dm));
1499   PetscCall(DMGetDimension(dm, &dim));
1500   PetscCall(PetscDualSpaceGetSection(sp, &section));
1501   PetscCall(PetscSectionGetStorageSize(section, &nDofs));
1502   PetscCall(DMPlexGetChart(dm, &pStart, &pEnd));
1503   PetscCall(PetscDualSpaceGetFormDegree(sp, &k));
1504   PetscCall(PetscDualSpaceGetNumComponents(sp, &Nc));
1505   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(k), &Nk));
1506   for (p = pStart, nNodes = 0, maxNzforms = 0; p < pEnd; p++) {
1507     PetscDualSpace  psp;
1508     DM              pdm;
1509     PetscInt        pdim, pNk;
1510     PetscQuadrature intNodes;
1511     Mat             intMat;
1512 
1513     PetscCall(PetscDualSpaceGetPointSubspace(sp, p, &psp));
1514     if (!psp) continue;
1515     PetscCall(PetscDualSpaceGetDM(psp, &pdm));
1516     PetscCall(DMGetDimension(pdm, &pdim));
1517     if (pdim < PetscAbsInt(k)) continue;
1518     PetscCall(PetscDTBinomialInt(pdim, PetscAbsInt(k), &pNk));
1519     PetscCall(PetscDualSpaceGetInteriorData(psp, &intNodes, &intMat));
1520     if (intNodes) {
1521       PetscInt nNodesp;
1522 
1523       PetscCall(PetscQuadratureGetData(intNodes, NULL, NULL, &nNodesp, NULL, NULL));
1524       nNodes += nNodesp;
1525     }
1526     if (intMat) {
1527       PetscInt maxNzsp;
1528       PetscInt maxNzformsp;
1529 
1530       PetscCall(MatSeqAIJGetMaxRowNonzeros(intMat, &maxNzsp));
1531       PetscCheck(maxNzsp % pNk == 0, PETSC_COMM_SELF, PETSC_ERR_PLIB, "interior matrix is not laid out as blocks of k-forms");
1532       maxNzformsp = maxNzsp / pNk;
1533       maxNzforms  = PetscMax(maxNzforms, maxNzformsp);
1534     }
1535   }
1536   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, nDofs, nNodes * Nc, maxNzforms * Nk, NULL, &allMat));
1537   PetscCall(PetscObjectSetOptionsPrefix((PetscObject)allMat, "ds_"));
1538   PetscCall(MatSetOption(allMat, MAT_IGNORE_ZERO_ENTRIES, PETSC_FALSE));
1539   PetscCall(PetscMalloc7(dim, &v0, dim, &pv0, dim * dim, &J, dim * dim, &Jinv, Nk * Nk, &L, maxNzforms * Nk, &work, maxNzforms * Nk, &iwork));
1540   for (j = 0; j < dim; j++) pv0[j] = -1.;
1541   PetscCall(PetscMalloc1(dim * nNodes, &nodes));
1542   for (p = pStart, countNodes = 0; p < pEnd; p++) {
1543     PetscDualSpace  psp;
1544     PetscQuadrature intNodes;
1545     DM              pdm;
1546     PetscInt        pdim, pNk;
1547     PetscInt        countNodesIn = countNodes;
1548     PetscReal       detJ;
1549     Mat             intMat;
1550 
1551     PetscCall(PetscDualSpaceGetPointSubspace(sp, p, &psp));
1552     if (!psp) continue;
1553     PetscCall(PetscDualSpaceGetDM(psp, &pdm));
1554     PetscCall(DMGetDimension(pdm, &pdim));
1555     if (pdim < PetscAbsInt(k)) continue;
1556     PetscCall(PetscDualSpaceGetInteriorData(psp, &intNodes, &intMat));
1557     if (intNodes == NULL && intMat == NULL) continue;
1558     PetscCall(PetscDTBinomialInt(pdim, PetscAbsInt(k), &pNk));
1559     if (p) {
1560       PetscCall(DMPlexComputeCellGeometryAffineFEM(dm, p, v0, J, Jinv, &detJ));
1561     } else { /* identity */
1562       PetscInt i, j;
1563 
1564       for (i = 0; i < dim; i++)
1565         for (j = 0; j < dim; j++) J[i * dim + j] = Jinv[i * dim + j] = 0.;
1566       for (i = 0; i < dim; i++) J[i * dim + i] = Jinv[i * dim + i] = 1.;
1567       for (i = 0; i < dim; i++) v0[i] = -1.;
1568     }
1569     if (pdim != dim) { /* compactify Jacobian */
1570       PetscInt i, j;
1571 
1572       for (i = 0; i < dim; i++)
1573         for (j = 0; j < pdim; j++) J[i * pdim + j] = J[i * dim + j];
1574     }
1575     PetscCall(PetscDTAltVPullbackMatrix(pdim, dim, J, k, L));
1576     if (intNodes) { /* push forward quadrature locations by the affine transformation */
1577       PetscInt         nNodesp;
1578       const PetscReal *nodesp;
1579       PetscInt         j;
1580 
1581       PetscCall(PetscQuadratureGetData(intNodes, NULL, NULL, &nNodesp, &nodesp, NULL));
1582       for (j = 0; j < nNodesp; j++, countNodes++) {
1583         PetscInt d, e;
1584 
1585         for (d = 0; d < dim; d++) {
1586           nodes[countNodes * dim + d] = v0[d];
1587           for (e = 0; e < pdim; e++) nodes[countNodes * dim + d] += J[d * pdim + e] * (nodesp[j * pdim + e] - pv0[e]);
1588         }
1589       }
1590     }
1591     if (intMat) {
1592       PetscInt nrows;
1593       PetscInt off;
1594 
1595       PetscCall(PetscSectionGetDof(section, p, &nrows));
1596       PetscCall(PetscSectionGetOffset(section, p, &off));
1597       for (j = 0; j < nrows; j++) {
1598         PetscInt           ncols;
1599         const PetscInt    *cols;
1600         const PetscScalar *vals;
1601         PetscInt           l, d, e;
1602         PetscInt           row = j + off;
1603 
1604         PetscCall(MatGetRow(intMat, j, &ncols, &cols, &vals));
1605         PetscCheck(ncols % pNk == 0, PETSC_COMM_SELF, PETSC_ERR_PLIB, "interior matrix is not laid out as blocks of k-forms");
1606         for (l = 0; l < ncols / pNk; l++) {
1607           PetscInt blockcol;
1608 
1609           for (d = 0; d < pNk; d++) PetscCheck((cols[l * pNk + d] % pNk) == d, PETSC_COMM_SELF, PETSC_ERR_PLIB, "interior matrix is not laid out as blocks of k-forms");
1610           blockcol = cols[l * pNk] / pNk;
1611           for (d = 0; d < Nk; d++) iwork[l * Nk + d] = (blockcol + countNodesIn) * Nk + d;
1612           for (d = 0; d < Nk; d++) work[l * Nk + d] = 0.;
1613           for (d = 0; d < Nk; d++) {
1614             for (e = 0; e < pNk; e++) {
1615               /* "push forward" dof by pulling back a k-form to be evaluated on the point: multiply on the right by L */
1616               work[l * Nk + d] += vals[l * pNk + e] * L[e * Nk + d];
1617             }
1618           }
1619         }
1620         PetscCall(MatSetValues(allMat, 1, &row, (ncols / pNk) * Nk, iwork, work, INSERT_VALUES));
1621         PetscCall(MatRestoreRow(intMat, j, &ncols, &cols, &vals));
1622       }
1623     }
1624   }
1625   PetscCall(MatAssemblyBegin(allMat, MAT_FINAL_ASSEMBLY));
1626   PetscCall(MatAssemblyEnd(allMat, MAT_FINAL_ASSEMBLY));
1627   PetscCall(PetscQuadratureCreate(PETSC_COMM_SELF, &allNodes));
1628   PetscCall(PetscQuadratureSetData(allNodes, dim, 0, nNodes, nodes, NULL));
1629   PetscCall(PetscFree7(v0, pv0, J, Jinv, L, work, iwork));
1630   PetscCall(MatDestroy(&sp->allMat));
1631   sp->allMat = allMat;
1632   PetscCall(PetscQuadratureDestroy(&sp->allNodes));
1633   sp->allNodes = allNodes;
1634   PetscFunctionReturn(PETSC_SUCCESS);
1635 }
1636 
1637 static PetscErrorCode PetscDualSpaceComputeFunctionalsFromAllData_Moments(PetscDualSpace sp)
1638 {
1639   Mat              allMat;
1640   PetscInt         momentOrder, i;
1641   PetscBool        tensor = PETSC_FALSE;
1642   const PetscReal *weights;
1643   PetscScalar     *array;
1644   PetscInt         nDofs;
1645   PetscInt         dim, Nc;
1646   DM               dm;
1647   PetscQuadrature  allNodes;
1648   PetscInt         nNodes;
1649 
1650   PetscFunctionBegin;
1651   PetscCall(PetscDualSpaceGetDM(sp, &dm));
1652   PetscCall(DMGetDimension(dm, &dim));
1653   PetscCall(PetscDualSpaceGetNumComponents(sp, &Nc));
1654   PetscCall(PetscDualSpaceGetAllData(sp, &allNodes, &allMat));
1655   PetscCall(MatGetSize(allMat, &nDofs, NULL));
1656   PetscCheck(nDofs == 1, PETSC_COMM_SELF, PETSC_ERR_SUP, "We do not yet support moments beyond P0, nDofs == %" PetscInt_FMT, nDofs);
1657   PetscCall(PetscMalloc1(nDofs, &sp->functional));
1658   PetscCall(PetscDualSpaceLagrangeGetMomentOrder(sp, &momentOrder));
1659   PetscCall(PetscDualSpaceLagrangeGetTensor(sp, &tensor));
1660   if (!tensor) PetscCall(PetscDTStroudConicalQuadrature(dim, Nc, PetscMax(momentOrder + 1, 1), -1.0, 1.0, &sp->functional[0]));
1661   else PetscCall(PetscDTGaussTensorQuadrature(dim, Nc, PetscMax(momentOrder + 1, 1), -1.0, 1.0, &sp->functional[0]));
1662   /* Need to replace allNodes and allMat */
1663   PetscCall(PetscObjectReference((PetscObject)sp->functional[0]));
1664   PetscCall(PetscQuadratureDestroy(&sp->allNodes));
1665   sp->allNodes = sp->functional[0];
1666   PetscCall(PetscQuadratureGetData(sp->allNodes, NULL, NULL, &nNodes, NULL, &weights));
1667   PetscCall(MatCreateSeqDense(PETSC_COMM_SELF, nDofs, nNodes * Nc, NULL, &allMat));
1668   PetscCall(PetscObjectSetOptionsPrefix((PetscObject)allMat, "ds_"));
1669   PetscCall(MatDenseGetArrayWrite(allMat, &array));
1670   for (i = 0; i < nNodes * Nc; ++i) array[i] = weights[i];
1671   PetscCall(MatDenseRestoreArrayWrite(allMat, &array));
1672   PetscCall(MatAssemblyBegin(allMat, MAT_FINAL_ASSEMBLY));
1673   PetscCall(MatAssemblyEnd(allMat, MAT_FINAL_ASSEMBLY));
1674   PetscCall(MatDestroy(&sp->allMat));
1675   sp->allMat = allMat;
1676   PetscFunctionReturn(PETSC_SUCCESS);
1677 }
1678 
1679 /* rather than trying to get all data from the functionals, we create
1680  * the functionals from rows of the quadrature -> dof matrix.
1681  *
1682  * Ideally most of the uses of PetscDualSpace in PetscFE will switch
1683  * to using intMat and allMat, so that the individual functionals
1684  * don't need to be constructed at all */
1685 PETSC_INTERN PetscErrorCode PetscDualSpaceComputeFunctionalsFromAllData(PetscDualSpace sp)
1686 {
1687   PetscQuadrature  allNodes;
1688   Mat              allMat;
1689   PetscInt         nDofs;
1690   PetscInt         dim, Nc, f;
1691   DM               dm;
1692   PetscInt         nNodes, spdim;
1693   const PetscReal *nodes = NULL;
1694   PetscSection     section;
1695   PetscBool        useMoments;
1696 
1697   PetscFunctionBegin;
1698   PetscCall(PetscDualSpaceGetDM(sp, &dm));
1699   PetscCall(DMGetDimension(dm, &dim));
1700   PetscCall(PetscDualSpaceGetNumComponents(sp, &Nc));
1701   PetscCall(PetscDualSpaceGetAllData(sp, &allNodes, &allMat));
1702   nNodes = 0;
1703   if (allNodes) PetscCall(PetscQuadratureGetData(allNodes, NULL, NULL, &nNodes, &nodes, NULL));
1704   PetscCall(MatGetSize(allMat, &nDofs, NULL));
1705   PetscCall(PetscDualSpaceGetSection(sp, &section));
1706   PetscCall(PetscSectionGetStorageSize(section, &spdim));
1707   PetscCheck(spdim == nDofs, PETSC_COMM_SELF, PETSC_ERR_PLIB, "incompatible all matrix size");
1708   PetscCall(PetscMalloc1(nDofs, &sp->functional));
1709   PetscCall(PetscDualSpaceLagrangeGetUseMoments(sp, &useMoments));
1710   for (f = 0; f < nDofs; f++) {
1711     PetscInt           ncols, c;
1712     const PetscInt    *cols;
1713     const PetscScalar *vals;
1714     PetscReal         *nodesf;
1715     PetscReal         *weightsf;
1716     PetscInt           nNodesf;
1717     PetscInt           countNodes;
1718 
1719     PetscCall(MatGetRow(allMat, f, &ncols, &cols, &vals));
1720     for (c = 1, nNodesf = 1; c < ncols; c++) {
1721       if ((cols[c] / Nc) != (cols[c - 1] / Nc)) nNodesf++;
1722     }
1723     PetscCall(PetscMalloc1(dim * nNodesf, &nodesf));
1724     PetscCall(PetscMalloc1(Nc * nNodesf, &weightsf));
1725     for (c = 0, countNodes = 0; c < ncols; c++) {
1726       if (!c || ((cols[c] / Nc) != (cols[c - 1] / Nc))) {
1727         PetscInt d;
1728 
1729         for (d = 0; d < Nc; d++) weightsf[countNodes * Nc + d] = 0.;
1730         for (d = 0; d < dim; d++) nodesf[countNodes * dim + d] = nodes[(cols[c] / Nc) * dim + d];
1731         countNodes++;
1732       }
1733       weightsf[(countNodes - 1) * Nc + (cols[c] % Nc)] = PetscRealPart(vals[c]);
1734     }
1735     PetscCall(PetscQuadratureCreate(PETSC_COMM_SELF, &sp->functional[f]));
1736     PetscCall(PetscQuadratureSetData(sp->functional[f], dim, Nc, nNodesf, nodesf, weightsf));
1737     PetscCall(MatRestoreRow(allMat, f, &ncols, &cols, &vals));
1738   }
1739   PetscFunctionReturn(PETSC_SUCCESS);
1740 }
1741 
1742 /* check if a cell is a tensor product of the segment with a facet,
1743  * specifically checking if f and f2 can be the "endpoints" (like the triangles
1744  * at either end of a wedge) */
1745 static PetscErrorCode DMPlexPointIsTensor_Internal_Given(DM dm, PetscInt p, PetscInt f, PetscInt f2, PetscBool *isTensor)
1746 {
1747   PetscInt        coneSize, c;
1748   const PetscInt *cone;
1749   const PetscInt *fCone;
1750   const PetscInt *f2Cone;
1751   PetscInt        fs[2];
1752   PetscInt        meetSize, nmeet;
1753   const PetscInt *meet;
1754 
1755   PetscFunctionBegin;
1756   fs[0] = f;
1757   fs[1] = f2;
1758   PetscCall(DMPlexGetMeet(dm, 2, fs, &meetSize, &meet));
1759   nmeet = meetSize;
1760   PetscCall(DMPlexRestoreMeet(dm, 2, fs, &meetSize, &meet));
1761   /* two points that have a non-empty meet cannot be at opposite ends of a cell */
1762   if (nmeet) {
1763     *isTensor = PETSC_FALSE;
1764     PetscFunctionReturn(PETSC_SUCCESS);
1765   }
1766   PetscCall(DMPlexGetConeSize(dm, p, &coneSize));
1767   PetscCall(DMPlexGetCone(dm, p, &cone));
1768   PetscCall(DMPlexGetCone(dm, f, &fCone));
1769   PetscCall(DMPlexGetCone(dm, f2, &f2Cone));
1770   for (c = 0; c < coneSize; c++) {
1771     PetscInt        e, ef;
1772     PetscInt        d = -1, d2 = -1;
1773     PetscInt        dcount, d2count;
1774     PetscInt        t = cone[c];
1775     PetscInt        tConeSize;
1776     PetscBool       tIsTensor;
1777     const PetscInt *tCone;
1778 
1779     if (t == f || t == f2) continue;
1780     /* for every other facet in the cone, check that is has
1781      * one ridge in common with each end */
1782     PetscCall(DMPlexGetConeSize(dm, t, &tConeSize));
1783     PetscCall(DMPlexGetCone(dm, t, &tCone));
1784 
1785     dcount  = 0;
1786     d2count = 0;
1787     for (e = 0; e < tConeSize; e++) {
1788       PetscInt q = tCone[e];
1789       for (ef = 0; ef < coneSize - 2; ef++) {
1790         if (fCone[ef] == q) {
1791           if (dcount) {
1792             *isTensor = PETSC_FALSE;
1793             PetscFunctionReturn(PETSC_SUCCESS);
1794           }
1795           d = q;
1796           dcount++;
1797         } else if (f2Cone[ef] == q) {
1798           if (d2count) {
1799             *isTensor = PETSC_FALSE;
1800             PetscFunctionReturn(PETSC_SUCCESS);
1801           }
1802           d2 = q;
1803           d2count++;
1804         }
1805       }
1806     }
1807     /* if the whole cell is a tensor with the segment, then this
1808      * facet should be a tensor with the segment */
1809     PetscCall(DMPlexPointIsTensor_Internal_Given(dm, t, d, d2, &tIsTensor));
1810     if (!tIsTensor) {
1811       *isTensor = PETSC_FALSE;
1812       PetscFunctionReturn(PETSC_SUCCESS);
1813     }
1814   }
1815   *isTensor = PETSC_TRUE;
1816   PetscFunctionReturn(PETSC_SUCCESS);
1817 }
1818 
1819 /* determine if a cell is a tensor with a segment by looping over pairs of facets to find a pair
1820  * that could be the opposite ends */
1821 static PetscErrorCode DMPlexPointIsTensor_Internal(DM dm, PetscInt p, PetscBool *isTensor, PetscInt *endA, PetscInt *endB)
1822 {
1823   PetscInt        coneSize, c, c2;
1824   const PetscInt *cone;
1825 
1826   PetscFunctionBegin;
1827   PetscCall(DMPlexGetConeSize(dm, p, &coneSize));
1828   if (!coneSize) {
1829     if (isTensor) *isTensor = PETSC_FALSE;
1830     if (endA) *endA = -1;
1831     if (endB) *endB = -1;
1832   }
1833   PetscCall(DMPlexGetCone(dm, p, &cone));
1834   for (c = 0; c < coneSize; c++) {
1835     PetscInt f = cone[c];
1836     PetscInt fConeSize;
1837 
1838     PetscCall(DMPlexGetConeSize(dm, f, &fConeSize));
1839     if (fConeSize != coneSize - 2) continue;
1840 
1841     for (c2 = c + 1; c2 < coneSize; c2++) {
1842       PetscInt  f2 = cone[c2];
1843       PetscBool isTensorff2;
1844       PetscInt  f2ConeSize;
1845 
1846       PetscCall(DMPlexGetConeSize(dm, f2, &f2ConeSize));
1847       if (f2ConeSize != coneSize - 2) continue;
1848 
1849       PetscCall(DMPlexPointIsTensor_Internal_Given(dm, p, f, f2, &isTensorff2));
1850       if (isTensorff2) {
1851         if (isTensor) *isTensor = PETSC_TRUE;
1852         if (endA) *endA = f;
1853         if (endB) *endB = f2;
1854         PetscFunctionReturn(PETSC_SUCCESS);
1855       }
1856     }
1857   }
1858   if (isTensor) *isTensor = PETSC_FALSE;
1859   if (endA) *endA = -1;
1860   if (endB) *endB = -1;
1861   PetscFunctionReturn(PETSC_SUCCESS);
1862 }
1863 
1864 /* determine if a cell is a tensor with a segment by looping over pairs of facets to find a pair
1865  * that could be the opposite ends */
1866 static PetscErrorCode DMPlexPointIsTensor(DM dm, PetscInt p, PetscBool *isTensor, PetscInt *endA, PetscInt *endB)
1867 {
1868   DMPlexInterpolatedFlag interpolated;
1869 
1870   PetscFunctionBegin;
1871   PetscCall(DMPlexIsInterpolated(dm, &interpolated));
1872   PetscCheck(interpolated == DMPLEX_INTERPOLATED_FULL, PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONGSTATE, "Only for interpolated DMPlex's");
1873   PetscCall(DMPlexPointIsTensor_Internal(dm, p, isTensor, endA, endB));
1874   PetscFunctionReturn(PETSC_SUCCESS);
1875 }
1876 
1877 /* Let k = formDegree and k' = -sign(k) * dim + k.  Transform a symmetric frame for k-forms on the biunit simplex into
1878  * a symmetric frame for k'-forms on the biunit simplex.
1879  *
1880  * A frame is "symmetric" if the pullback of every symmetry of the biunit simplex is a permutation of the frame.
1881  *
1882  * forms in the symmetric frame are used as dofs in the untrimmed simplex spaces.  This way, symmetries of the
1883  * reference cell result in permutations of dofs grouped by node.
1884  *
1885  * Use T to transform dof matrices for k'-forms into dof matrices for k-forms as a block diagonal transformation on
1886  * the right.
1887  */
1888 static PetscErrorCode BiunitSimplexSymmetricFormTransformation(PetscInt dim, PetscInt formDegree, PetscReal T[])
1889 {
1890   PetscInt   k  = formDegree;
1891   PetscInt   kd = k < 0 ? dim + k : k - dim;
1892   PetscInt   Nk;
1893   PetscReal *biToEq, *eqToBi, *biToEqStar, *eqToBiStar;
1894   PetscInt   fact;
1895 
1896   PetscFunctionBegin;
1897   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(k), &Nk));
1898   PetscCall(PetscCalloc4(dim * dim, &biToEq, dim * dim, &eqToBi, Nk * Nk, &biToEqStar, Nk * Nk, &eqToBiStar));
1899   /* fill in biToEq: Jacobian of the transformation from the biunit simplex to the equilateral simplex */
1900   fact = 0;
1901   for (PetscInt i = 0; i < dim; i++) {
1902     biToEq[i * dim + i] = PetscSqrtReal(((PetscReal)i + 2.) / (2. * ((PetscReal)i + 1.)));
1903     fact += 4 * (i + 1);
1904     for (PetscInt j = i + 1; j < dim; j++) biToEq[i * dim + j] = PetscSqrtReal(1. / (PetscReal)fact);
1905   }
1906   /* fill in eqToBi: Jacobian of the transformation from the equilateral simplex to the biunit simplex */
1907   fact = 0;
1908   for (PetscInt j = 0; j < dim; j++) {
1909     eqToBi[j * dim + j] = PetscSqrtReal(2. * ((PetscReal)j + 1.) / ((PetscReal)j + 2));
1910     fact += j + 1;
1911     for (PetscInt i = 0; i < j; i++) eqToBi[i * dim + j] = -PetscSqrtReal(1. / (PetscReal)fact);
1912   }
1913   PetscCall(PetscDTAltVPullbackMatrix(dim, dim, biToEq, kd, biToEqStar));
1914   PetscCall(PetscDTAltVPullbackMatrix(dim, dim, eqToBi, k, eqToBiStar));
1915   /* product of pullbacks simulates the following steps
1916    *
1917    * 1. start with frame W = [w_1, w_2, ..., w_m] of k forms that is symmetric on the biunit simplex:
1918           if J is the Jacobian of a symmetry of the biunit simplex, then J_k* W = [J_k*w_1, ..., J_k*w_m]
1919           is a permutation of W.
1920           Even though a k' form --- a (dim - k) form represented by its Hodge star --- has the same geometric
1921           content as a k form, W is not a symmetric frame of k' forms on the biunit simplex.  That's because,
1922           for general Jacobian J, J_k* != J_k'*.
1923    * 2. pullback W to the equilateral triangle using the k pullback, W_eq = eqToBi_k* W.  All symmetries of the
1924           equilateral simplex have orthonormal Jacobians.  For an orthonormal Jacobian O, J_k* = J_k'*, so W_eq is
1925           also a symmetric frame for k' forms on the equilateral simplex.
1926      3. pullback W_eq back to the biunit simplex using the k' pulback, V = biToEq_k'* W_eq = biToEq_k'* eqToBi_k* W.
1927           V is a symmetric frame for k' forms on the biunit simplex.
1928    */
1929   for (PetscInt i = 0; i < Nk; i++) {
1930     for (PetscInt j = 0; j < Nk; j++) {
1931       PetscReal val = 0.;
1932       for (PetscInt k = 0; k < Nk; k++) val += biToEqStar[i * Nk + k] * eqToBiStar[k * Nk + j];
1933       T[i * Nk + j] = val;
1934     }
1935   }
1936   PetscCall(PetscFree4(biToEq, eqToBi, biToEqStar, eqToBiStar));
1937   PetscFunctionReturn(PETSC_SUCCESS);
1938 }
1939 
1940 /* permute a quadrature -> dof matrix so that its rows are in revlex order by nodeIdx */
1941 static PetscErrorCode MatPermuteByNodeIdx(Mat A, PetscLagNodeIndices ni, Mat *Aperm)
1942 {
1943   PetscInt   m, n, i, j;
1944   PetscInt   nodeIdxDim = ni->nodeIdxDim;
1945   PetscInt   nodeVecDim = ni->nodeVecDim;
1946   PetscInt  *perm;
1947   IS         permIS;
1948   IS         id;
1949   PetscInt  *nIdxPerm;
1950   PetscReal *nVecPerm;
1951 
1952   PetscFunctionBegin;
1953   PetscCall(PetscLagNodeIndicesGetPermutation(ni, &perm));
1954   PetscCall(MatGetSize(A, &m, &n));
1955   PetscCall(PetscMalloc1(nodeIdxDim * m, &nIdxPerm));
1956   PetscCall(PetscMalloc1(nodeVecDim * m, &nVecPerm));
1957   for (i = 0; i < m; i++)
1958     for (j = 0; j < nodeIdxDim; j++) nIdxPerm[i * nodeIdxDim + j] = ni->nodeIdx[perm[i] * nodeIdxDim + j];
1959   for (i = 0; i < m; i++)
1960     for (j = 0; j < nodeVecDim; j++) nVecPerm[i * nodeVecDim + j] = ni->nodeVec[perm[i] * nodeVecDim + j];
1961   PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m, perm, PETSC_USE_POINTER, &permIS));
1962   PetscCall(ISSetPermutation(permIS));
1963   PetscCall(ISCreateStride(PETSC_COMM_SELF, n, 0, 1, &id));
1964   PetscCall(ISSetPermutation(id));
1965   PetscCall(MatPermute(A, permIS, id, Aperm));
1966   PetscCall(ISDestroy(&permIS));
1967   PetscCall(ISDestroy(&id));
1968   for (i = 0; i < m; i++) perm[i] = i;
1969   PetscCall(PetscFree(ni->nodeIdx));
1970   PetscCall(PetscFree(ni->nodeVec));
1971   ni->nodeIdx = nIdxPerm;
1972   ni->nodeVec = nVecPerm;
1973   PetscFunctionReturn(PETSC_SUCCESS);
1974 }
1975 
1976 static PetscErrorCode PetscDualSpaceSetUp_Lagrange(PetscDualSpace sp)
1977 {
1978   PetscDualSpace_Lag    *lag   = (PetscDualSpace_Lag *)sp->data;
1979   DM                     dm    = sp->dm;
1980   DM                     dmint = NULL;
1981   PetscInt               order;
1982   PetscInt               Nc;
1983   MPI_Comm               comm;
1984   PetscBool              continuous;
1985   PetscSection           section;
1986   PetscInt               depth, dim, pStart, pEnd, cStart, cEnd, p, *pStratStart, *pStratEnd, d;
1987   PetscInt               formDegree, Nk, Ncopies;
1988   PetscInt               tensorf = -1, tensorf2 = -1;
1989   PetscBool              tensorCell, tensorSpace;
1990   PetscBool              uniform, trimmed;
1991   Petsc1DNodeFamily      nodeFamily;
1992   PetscInt               numNodeSkip;
1993   DMPlexInterpolatedFlag interpolated;
1994   PetscBool              isbdm;
1995 
1996   PetscFunctionBegin;
1997   /* step 1: sanitize input */
1998   PetscCall(PetscObjectGetComm((PetscObject)sp, &comm));
1999   PetscCall(DMGetDimension(dm, &dim));
2000   PetscCall(PetscObjectTypeCompare((PetscObject)sp, PETSCDUALSPACEBDM, &isbdm));
2001   if (isbdm) {
2002     sp->k = -(dim - 1); /* form degree of H-div */
2003     PetscCall(PetscObjectChangeTypeName((PetscObject)sp, PETSCDUALSPACELAGRANGE));
2004   }
2005   PetscCall(PetscDualSpaceGetFormDegree(sp, &formDegree));
2006   PetscCheck(PetscAbsInt(formDegree) <= dim, comm, PETSC_ERR_ARG_OUTOFRANGE, "Form degree must be bounded by dimension");
2007   PetscCall(PetscDTBinomialInt(dim, PetscAbsInt(formDegree), &Nk));
2008   if (sp->Nc <= 0 && lag->numCopies > 0) sp->Nc = Nk * lag->numCopies;
2009   Nc = sp->Nc;
2010   PetscCheck(Nc % Nk == 0, comm, PETSC_ERR_ARG_INCOMP, "Number of components is not a multiple of form degree size");
2011   if (lag->numCopies <= 0) lag->numCopies = Nc / Nk;
2012   Ncopies = lag->numCopies;
2013   PetscCheck(Nc / Nk == Ncopies, comm, PETSC_ERR_ARG_INCOMP, "Number of copies * (dim choose k) != Nc");
2014   if (!dim) sp->order = 0;
2015   order   = sp->order;
2016   uniform = sp->uniform;
2017   PetscCheck(uniform, PETSC_COMM_SELF, PETSC_ERR_SUP, "Variable order not supported yet");
2018   if (lag->trimmed && !formDegree) lag->trimmed = PETSC_FALSE; /* trimmed spaces are the same as full spaces for 0-forms */
2019   if (lag->nodeType == PETSCDTNODES_DEFAULT) {
2020     lag->nodeType     = PETSCDTNODES_GAUSSJACOBI;
2021     lag->nodeExponent = 0.;
2022     /* trimmed spaces don't include corner vertices, so don't use end nodes by default */
2023     lag->endNodes = lag->trimmed ? PETSC_FALSE : PETSC_TRUE;
2024   }
2025   /* If a trimmed space and the user did choose nodes with endpoints, skip them by default */
2026   if (lag->numNodeSkip < 0) lag->numNodeSkip = (lag->trimmed && lag->endNodes) ? 1 : 0;
2027   numNodeSkip = lag->numNodeSkip;
2028   PetscCheck(!lag->trimmed || order, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Cannot have zeroth order trimmed elements");
2029   if (lag->trimmed && PetscAbsInt(formDegree) == dim) { /* convert trimmed n-forms to untrimmed of one polynomial order less */
2030     sp->order--;
2031     order--;
2032     lag->trimmed = PETSC_FALSE;
2033   }
2034   trimmed = lag->trimmed;
2035   if (!order || PetscAbsInt(formDegree) == dim) lag->continuous = PETSC_FALSE;
2036   continuous = lag->continuous;
2037   PetscCall(DMPlexGetDepth(dm, &depth));
2038   PetscCall(DMPlexGetChart(dm, &pStart, &pEnd));
2039   PetscCall(DMPlexGetHeightStratum(dm, 0, &cStart, &cEnd));
2040   PetscCheck(pStart == 0 && cStart == 0, PetscObjectComm((PetscObject)sp), PETSC_ERR_ARG_WRONGSTATE, "Expect DM with chart starting at zero and cells first");
2041   PetscCheck(cEnd == 1, PetscObjectComm((PetscObject)sp), PETSC_ERR_ARG_WRONGSTATE, "Use PETSCDUALSPACEREFINED for multi-cell reference meshes");
2042   PetscCall(DMPlexIsInterpolated(dm, &interpolated));
2043   if (interpolated != DMPLEX_INTERPOLATED_FULL) {
2044     PetscCall(DMPlexInterpolate(dm, &dmint));
2045   } else {
2046     PetscCall(PetscObjectReference((PetscObject)dm));
2047     dmint = dm;
2048   }
2049   tensorCell = PETSC_FALSE;
2050   if (dim > 1) PetscCall(DMPlexPointIsTensor(dmint, 0, &tensorCell, &tensorf, &tensorf2));
2051   lag->tensorCell = tensorCell;
2052   if (dim < 2 || !lag->tensorCell) lag->tensorSpace = PETSC_FALSE;
2053   tensorSpace = lag->tensorSpace;
2054   if (!lag->nodeFamily) PetscCall(Petsc1DNodeFamilyCreate(lag->nodeType, lag->nodeExponent, lag->endNodes, &lag->nodeFamily));
2055   nodeFamily = lag->nodeFamily;
2056   PetscCheck(interpolated == DMPLEX_INTERPOLATED_FULL || !continuous || (PetscAbsInt(formDegree) <= 0 && order <= 1), PETSC_COMM_SELF, PETSC_ERR_PLIB, "Reference element won't support all boundary nodes");
2057 
2058   if (Ncopies > 1) {
2059     PetscDualSpace scalarsp;
2060 
2061     PetscCall(PetscDualSpaceDuplicate(sp, &scalarsp));
2062     /* Setting the number of components to Nk is a space with 1 copy of each k-form */
2063     sp->setupcalled = PETSC_FALSE;
2064     PetscCall(PetscDualSpaceSetNumComponents(scalarsp, Nk));
2065     PetscCall(PetscDualSpaceSetUp(scalarsp));
2066     PetscCall(PetscDualSpaceSetType(sp, PETSCDUALSPACESUM));
2067     PetscCall(PetscDualSpaceSumSetNumSubspaces(sp, Ncopies));
2068     PetscCall(PetscDualSpaceSumSetConcatenate(sp, PETSC_TRUE));
2069     PetscCall(PetscDualSpaceSumSetInterleave(sp, PETSC_TRUE, PETSC_FALSE));
2070     for (PetscInt i = 0; i < Ncopies; i++) PetscCall(PetscDualSpaceSumSetSubspace(sp, i, scalarsp));
2071     PetscCall(PetscDualSpaceSetUp(sp));
2072     PetscCall(PetscDualSpaceDestroy(&scalarsp));
2073     PetscCall(DMDestroy(&dmint));
2074     PetscFunctionReturn(PETSC_SUCCESS);
2075   }
2076 
2077   /* step 2: construct the boundary spaces */
2078   PetscCall(PetscMalloc2(depth + 1, &pStratStart, depth + 1, &pStratEnd));
2079   PetscCall(PetscCalloc1(pEnd, &sp->pointSpaces));
2080   for (d = 0; d <= depth; ++d) PetscCall(DMPlexGetDepthStratum(dm, d, &pStratStart[d], &pStratEnd[d]));
2081   PetscCall(PetscDualSpaceSectionCreate_Internal(sp, &section));
2082   sp->pointSection = section;
2083   if (continuous && !lag->interiorOnly) {
2084     PetscInt h;
2085 
2086     for (p = pStratStart[depth - 1]; p < pStratEnd[depth - 1]; p++) { /* calculate the facet dual spaces */
2087       PetscReal      v0[3];
2088       DMPolytopeType ptype;
2089       PetscReal      J[9], detJ;
2090       PetscInt       q;
2091 
2092       PetscCall(DMPlexComputeCellGeometryAffineFEM(dm, p, v0, J, NULL, &detJ));
2093       PetscCall(DMPlexGetCellType(dm, p, &ptype));
2094 
2095       /* compare to previous facets: if computed, reference that dualspace */
2096       for (q = pStratStart[depth - 1]; q < p; q++) {
2097         DMPolytopeType qtype;
2098 
2099         PetscCall(DMPlexGetCellType(dm, q, &qtype));
2100         if (qtype == ptype) break;
2101       }
2102       if (q < p) { /* this facet has the same dual space as that one */
2103         PetscCall(PetscObjectReference((PetscObject)sp->pointSpaces[q]));
2104         sp->pointSpaces[p] = sp->pointSpaces[q];
2105         continue;
2106       }
2107       /* if not, recursively compute this dual space */
2108       PetscCall(PetscDualSpaceCreateFacetSubspace_Lagrange(sp, NULL, p, formDegree, Ncopies, PETSC_FALSE, &sp->pointSpaces[p]));
2109     }
2110     for (h = 2; h <= depth; h++) { /* get the higher subspaces from the facet subspaces */
2111       PetscInt hd   = depth - h;
2112       PetscInt hdim = dim - h;
2113 
2114       if (hdim < PetscAbsInt(formDegree)) break;
2115       for (p = pStratStart[hd]; p < pStratEnd[hd]; p++) {
2116         PetscInt        suppSize, s;
2117         const PetscInt *supp;
2118 
2119         PetscCall(DMPlexGetSupportSize(dm, p, &suppSize));
2120         PetscCall(DMPlexGetSupport(dm, p, &supp));
2121         for (s = 0; s < suppSize; s++) {
2122           DM              qdm;
2123           PetscDualSpace  qsp, psp;
2124           PetscInt        c, coneSize, q;
2125           const PetscInt *cone;
2126           const PetscInt *refCone;
2127 
2128           q   = supp[s];
2129           qsp = sp->pointSpaces[q];
2130           PetscCall(DMPlexGetConeSize(dm, q, &coneSize));
2131           PetscCall(DMPlexGetCone(dm, q, &cone));
2132           for (c = 0; c < coneSize; c++)
2133             if (cone[c] == p) break;
2134           PetscCheck(c != coneSize, PetscObjectComm((PetscObject)dm), PETSC_ERR_PLIB, "cone/support mismatch");
2135           PetscCall(PetscDualSpaceGetDM(qsp, &qdm));
2136           PetscCall(DMPlexGetCone(qdm, 0, &refCone));
2137           /* get the equivalent dual space from the support dual space */
2138           PetscCall(PetscDualSpaceGetPointSubspace(qsp, refCone[c], &psp));
2139           if (!s) {
2140             PetscCall(PetscObjectReference((PetscObject)psp));
2141             sp->pointSpaces[p] = psp;
2142           }
2143         }
2144       }
2145     }
2146     for (p = 1; p < pEnd; p++) {
2147       PetscInt pspdim;
2148       if (!sp->pointSpaces[p]) continue;
2149       PetscCall(PetscDualSpaceGetInteriorDimension(sp->pointSpaces[p], &pspdim));
2150       PetscCall(PetscSectionSetDof(section, p, pspdim));
2151     }
2152   }
2153 
2154   if (trimmed && !continuous) {
2155     /* the dofs of a trimmed space don't have a nice tensor/lattice structure:
2156      * just construct the continuous dual space and copy all of the data over,
2157      * allocating it all to the cell instead of splitting it up between the boundaries */
2158     PetscDualSpace      spcont;
2159     PetscInt            spdim, f;
2160     PetscQuadrature     allNodes;
2161     PetscDualSpace_Lag *lagc;
2162     Mat                 allMat;
2163 
2164     PetscCall(PetscDualSpaceDuplicate(sp, &spcont));
2165     PetscCall(PetscDualSpaceLagrangeSetContinuity(spcont, PETSC_TRUE));
2166     PetscCall(PetscDualSpaceSetUp(spcont));
2167     PetscCall(PetscDualSpaceGetDimension(spcont, &spdim));
2168     sp->spdim = sp->spintdim = spdim;
2169     PetscCall(PetscSectionSetDof(section, 0, spdim));
2170     PetscCall(PetscDualSpaceSectionSetUp_Internal(sp, section));
2171     PetscCall(PetscMalloc1(spdim, &sp->functional));
2172     for (f = 0; f < spdim; f++) {
2173       PetscQuadrature fn;
2174 
2175       PetscCall(PetscDualSpaceGetFunctional(spcont, f, &fn));
2176       PetscCall(PetscObjectReference((PetscObject)fn));
2177       sp->functional[f] = fn;
2178     }
2179     PetscCall(PetscDualSpaceGetAllData(spcont, &allNodes, &allMat));
2180     PetscCall(PetscObjectReference((PetscObject)allNodes));
2181     PetscCall(PetscObjectReference((PetscObject)allNodes));
2182     sp->allNodes = sp->intNodes = allNodes;
2183     PetscCall(PetscObjectReference((PetscObject)allMat));
2184     PetscCall(PetscObjectReference((PetscObject)allMat));
2185     sp->allMat = sp->intMat = allMat;
2186     lagc                    = (PetscDualSpace_Lag *)spcont->data;
2187     PetscCall(PetscLagNodeIndicesReference(lagc->vertIndices));
2188     lag->vertIndices = lagc->vertIndices;
2189     PetscCall(PetscLagNodeIndicesReference(lagc->allNodeIndices));
2190     PetscCall(PetscLagNodeIndicesReference(lagc->allNodeIndices));
2191     lag->intNodeIndices = lagc->allNodeIndices;
2192     lag->allNodeIndices = lagc->allNodeIndices;
2193     PetscCall(PetscDualSpaceDestroy(&spcont));
2194     PetscCall(PetscFree2(pStratStart, pStratEnd));
2195     PetscCall(DMDestroy(&dmint));
2196     PetscFunctionReturn(PETSC_SUCCESS);
2197   }
2198 
2199   /* step 3: construct intNodes, and intMat, and combine it with boundray data to make allNodes and allMat */
2200   if (!tensorSpace) {
2201     if (!tensorCell) PetscCall(PetscLagNodeIndicesCreateSimplexVertices(dm, &lag->vertIndices));
2202 
2203     if (trimmed) {
2204       /* there is one dof in the interior of the a trimmed element for each full polynomial of with degree at most
2205        * order + k - dim - 1 */
2206       if (order + PetscAbsInt(formDegree) > dim) {
2207         PetscInt sum = order + PetscAbsInt(formDegree) - dim - 1;
2208         PetscInt nDofs;
2209 
2210         PetscCall(PetscDualSpaceLagrangeCreateSimplexNodeMat(nodeFamily, dim, sum, Nk, numNodeSkip, &sp->intNodes, &sp->intMat, &lag->intNodeIndices));
2211         PetscCall(MatGetSize(sp->intMat, &nDofs, NULL));
2212         PetscCall(PetscSectionSetDof(section, 0, nDofs));
2213       }
2214       PetscCall(PetscDualSpaceSectionSetUp_Internal(sp, section));
2215       PetscCall(PetscDualSpaceCreateAllDataFromInteriorData(sp));
2216       PetscCall(PetscDualSpaceLagrangeCreateAllNodeIdx(sp));
2217     } else {
2218       if (!continuous) {
2219         /* if discontinuous just construct one node for each set of dofs (a set of dofs is a basis for the k-form
2220          * space) */
2221         PetscInt sum = order;
2222         PetscInt nDofs;
2223 
2224         PetscCall(PetscDualSpaceLagrangeCreateSimplexNodeMat(nodeFamily, dim, sum, Nk, numNodeSkip, &sp->intNodes, &sp->intMat, &lag->intNodeIndices));
2225         PetscCall(MatGetSize(sp->intMat, &nDofs, NULL));
2226         PetscCall(PetscSectionSetDof(section, 0, nDofs));
2227         PetscCall(PetscDualSpaceSectionSetUp_Internal(sp, section));
2228         PetscCall(PetscObjectReference((PetscObject)sp->intNodes));
2229         sp->allNodes = sp->intNodes;
2230         PetscCall(PetscObjectReference((PetscObject)sp->intMat));
2231         sp->allMat = sp->intMat;
2232         PetscCall(PetscLagNodeIndicesReference(lag->intNodeIndices));
2233         lag->allNodeIndices = lag->intNodeIndices;
2234       } else {
2235         /* there is one dof in the interior of the a full element for each trimmed polynomial of with degree at most
2236          * order + k - dim, but with complementary form degree */
2237         if (order + PetscAbsInt(formDegree) > dim) {
2238           PetscDualSpace      trimmedsp;
2239           PetscDualSpace_Lag *trimmedlag;
2240           PetscQuadrature     intNodes;
2241           PetscInt            trFormDegree = formDegree >= 0 ? formDegree - dim : dim - PetscAbsInt(formDegree);
2242           PetscInt            nDofs;
2243           Mat                 intMat;
2244 
2245           PetscCall(PetscDualSpaceDuplicate(sp, &trimmedsp));
2246           PetscCall(PetscDualSpaceLagrangeSetTrimmed(trimmedsp, PETSC_TRUE));
2247           PetscCall(PetscDualSpaceSetOrder(trimmedsp, order + PetscAbsInt(formDegree) - dim));
2248           PetscCall(PetscDualSpaceSetFormDegree(trimmedsp, trFormDegree));
2249           trimmedlag              = (PetscDualSpace_Lag *)trimmedsp->data;
2250           trimmedlag->numNodeSkip = numNodeSkip + 1;
2251           PetscCall(PetscDualSpaceSetUp(trimmedsp));
2252           PetscCall(PetscDualSpaceGetAllData(trimmedsp, &intNodes, &intMat));
2253           PetscCall(PetscObjectReference((PetscObject)intNodes));
2254           sp->intNodes = intNodes;
2255           PetscCall(PetscLagNodeIndicesReference(trimmedlag->allNodeIndices));
2256           lag->intNodeIndices = trimmedlag->allNodeIndices;
2257           PetscCall(PetscObjectReference((PetscObject)intMat));
2258           if (PetscAbsInt(formDegree) > 0 && PetscAbsInt(formDegree) < dim) {
2259             PetscReal   *T;
2260             PetscScalar *work;
2261             PetscInt     nCols, nRows;
2262             Mat          intMatT;
2263 
2264             PetscCall(MatDuplicate(intMat, MAT_COPY_VALUES, &intMatT));
2265             PetscCall(MatGetSize(intMat, &nRows, &nCols));
2266             PetscCall(PetscMalloc2(Nk * Nk, &T, nCols, &work));
2267             PetscCall(BiunitSimplexSymmetricFormTransformation(dim, formDegree, T));
2268             for (PetscInt row = 0; row < nRows; row++) {
2269               PetscInt           nrCols;
2270               const PetscInt    *rCols;
2271               const PetscScalar *rVals;
2272 
2273               PetscCall(MatGetRow(intMat, row, &nrCols, &rCols, &rVals));
2274               PetscCheck(nrCols % Nk == 0, PETSC_COMM_SELF, PETSC_ERR_PLIB, "nonzeros in intMat matrix are not in k-form size blocks");
2275               for (PetscInt b = 0; b < nrCols; b += Nk) {
2276                 const PetscScalar *v = &rVals[b];
2277                 PetscScalar       *w = &work[b];
2278                 for (PetscInt j = 0; j < Nk; j++) {
2279                   w[j] = 0.;
2280                   for (PetscInt i = 0; i < Nk; i++) w[j] += v[i] * T[i * Nk + j];
2281                 }
2282               }
2283               PetscCall(MatSetValuesBlocked(intMatT, 1, &row, nrCols, rCols, work, INSERT_VALUES));
2284               PetscCall(MatRestoreRow(intMat, row, &nrCols, &rCols, &rVals));
2285             }
2286             PetscCall(MatAssemblyBegin(intMatT, MAT_FINAL_ASSEMBLY));
2287             PetscCall(MatAssemblyEnd(intMatT, MAT_FINAL_ASSEMBLY));
2288             PetscCall(MatDestroy(&intMat));
2289             intMat = intMatT;
2290             PetscCall(PetscLagNodeIndicesDestroy(&lag->intNodeIndices));
2291             PetscCall(PetscLagNodeIndicesDuplicate(trimmedlag->allNodeIndices, &lag->intNodeIndices));
2292             {
2293               PetscInt         nNodes     = lag->intNodeIndices->nNodes;
2294               PetscReal       *newNodeVec = lag->intNodeIndices->nodeVec;
2295               const PetscReal *oldNodeVec = trimmedlag->allNodeIndices->nodeVec;
2296 
2297               for (PetscInt n = 0; n < nNodes; n++) {
2298                 PetscReal       *w = &newNodeVec[n * Nk];
2299                 const PetscReal *v = &oldNodeVec[n * Nk];
2300 
2301                 for (PetscInt j = 0; j < Nk; j++) {
2302                   w[j] = 0.;
2303                   for (PetscInt i = 0; i < Nk; i++) w[j] += v[i] * T[i * Nk + j];
2304                 }
2305               }
2306             }
2307             PetscCall(PetscFree2(T, work));
2308           }
2309           sp->intMat = intMat;
2310           PetscCall(MatGetSize(sp->intMat, &nDofs, NULL));
2311           PetscCall(PetscDualSpaceDestroy(&trimmedsp));
2312           PetscCall(PetscSectionSetDof(section, 0, nDofs));
2313         }
2314         PetscCall(PetscDualSpaceSectionSetUp_Internal(sp, section));
2315         PetscCall(PetscDualSpaceCreateAllDataFromInteriorData(sp));
2316         PetscCall(PetscDualSpaceLagrangeCreateAllNodeIdx(sp));
2317       }
2318     }
2319   } else {
2320     PetscQuadrature     intNodesTrace  = NULL;
2321     PetscQuadrature     intNodesFiber  = NULL;
2322     PetscQuadrature     intNodes       = NULL;
2323     PetscLagNodeIndices intNodeIndices = NULL;
2324     Mat                 intMat         = NULL;
2325 
2326     if (PetscAbsInt(formDegree) < dim) { /* get the trace k-forms on the first facet, and the 0-forms on the edge,
2327                                             and wedge them together to create some of the k-form dofs */
2328       PetscDualSpace      trace, fiber;
2329       PetscDualSpace_Lag *tracel, *fiberl;
2330       Mat                 intMatTrace, intMatFiber;
2331 
2332       if (sp->pointSpaces[tensorf]) {
2333         PetscCall(PetscObjectReference((PetscObject)sp->pointSpaces[tensorf]));
2334         trace = sp->pointSpaces[tensorf];
2335       } else {
2336         PetscCall(PetscDualSpaceCreateFacetSubspace_Lagrange(sp, NULL, tensorf, formDegree, Ncopies, PETSC_TRUE, &trace));
2337       }
2338       PetscCall(PetscDualSpaceCreateEdgeSubspace_Lagrange(sp, order, 0, 1, PETSC_TRUE, &fiber));
2339       tracel = (PetscDualSpace_Lag *)trace->data;
2340       fiberl = (PetscDualSpace_Lag *)fiber->data;
2341       PetscCall(PetscLagNodeIndicesCreateTensorVertices(dm, tracel->vertIndices, &lag->vertIndices));
2342       PetscCall(PetscDualSpaceGetInteriorData(trace, &intNodesTrace, &intMatTrace));
2343       PetscCall(PetscDualSpaceGetInteriorData(fiber, &intNodesFiber, &intMatFiber));
2344       if (intNodesTrace && intNodesFiber) {
2345         PetscCall(PetscQuadratureCreateTensor(intNodesTrace, intNodesFiber, &intNodes));
2346         PetscCall(MatTensorAltV(intMatTrace, intMatFiber, dim - 1, formDegree, 1, 0, &intMat));
2347         PetscCall(PetscLagNodeIndicesTensor(tracel->intNodeIndices, dim - 1, formDegree, fiberl->intNodeIndices, 1, 0, &intNodeIndices));
2348       }
2349       PetscCall(PetscObjectReference((PetscObject)intNodesTrace));
2350       PetscCall(PetscObjectReference((PetscObject)intNodesFiber));
2351       PetscCall(PetscDualSpaceDestroy(&fiber));
2352       PetscCall(PetscDualSpaceDestroy(&trace));
2353     }
2354     if (PetscAbsInt(formDegree) > 0) { /* get the trace (k-1)-forms on the first facet, and the 1-forms on the edge,
2355                                           and wedge them together to create the remaining k-form dofs */
2356       PetscDualSpace      trace, fiber;
2357       PetscDualSpace_Lag *tracel, *fiberl;
2358       PetscQuadrature     intNodesTrace2, intNodesFiber2, intNodes2;
2359       PetscLagNodeIndices intNodeIndices2;
2360       Mat                 intMatTrace, intMatFiber, intMat2;
2361       PetscInt            traceDegree = formDegree > 0 ? formDegree - 1 : formDegree + 1;
2362       PetscInt            fiberDegree = formDegree > 0 ? 1 : -1;
2363 
2364       PetscCall(PetscDualSpaceCreateFacetSubspace_Lagrange(sp, NULL, tensorf, traceDegree, Ncopies, PETSC_TRUE, &trace));
2365       PetscCall(PetscDualSpaceCreateEdgeSubspace_Lagrange(sp, order, fiberDegree, 1, PETSC_TRUE, &fiber));
2366       tracel = (PetscDualSpace_Lag *)trace->data;
2367       fiberl = (PetscDualSpace_Lag *)fiber->data;
2368       if (!lag->vertIndices) PetscCall(PetscLagNodeIndicesCreateTensorVertices(dm, tracel->vertIndices, &lag->vertIndices));
2369       PetscCall(PetscDualSpaceGetInteriorData(trace, &intNodesTrace2, &intMatTrace));
2370       PetscCall(PetscDualSpaceGetInteriorData(fiber, &intNodesFiber2, &intMatFiber));
2371       if (intNodesTrace2 && intNodesFiber2) {
2372         PetscCall(PetscQuadratureCreateTensor(intNodesTrace2, intNodesFiber2, &intNodes2));
2373         PetscCall(MatTensorAltV(intMatTrace, intMatFiber, dim - 1, traceDegree, 1, fiberDegree, &intMat2));
2374         PetscCall(PetscLagNodeIndicesTensor(tracel->intNodeIndices, dim - 1, traceDegree, fiberl->intNodeIndices, 1, fiberDegree, &intNodeIndices2));
2375         if (!intMat) {
2376           intMat         = intMat2;
2377           intNodes       = intNodes2;
2378           intNodeIndices = intNodeIndices2;
2379         } else {
2380           /* merge the matrices, quadrature points, and nodes */
2381           PetscInt            nM;
2382           PetscInt            nDof, nDof2;
2383           PetscInt           *toMerged = NULL, *toMerged2 = NULL;
2384           PetscQuadrature     merged               = NULL;
2385           PetscLagNodeIndices intNodeIndicesMerged = NULL;
2386           Mat                 matMerged            = NULL;
2387 
2388           PetscCall(MatGetSize(intMat, &nDof, NULL));
2389           PetscCall(MatGetSize(intMat2, &nDof2, NULL));
2390           PetscCall(PetscQuadraturePointsMerge(intNodes, intNodes2, &merged, &toMerged, &toMerged2));
2391           PetscCall(PetscQuadratureGetData(merged, NULL, NULL, &nM, NULL, NULL));
2392           PetscCall(MatricesMerge(intMat, intMat2, dim, formDegree, nM, toMerged, toMerged2, &matMerged));
2393           PetscCall(PetscLagNodeIndicesMerge(intNodeIndices, intNodeIndices2, &intNodeIndicesMerged));
2394           PetscCall(PetscFree(toMerged));
2395           PetscCall(PetscFree(toMerged2));
2396           PetscCall(MatDestroy(&intMat));
2397           PetscCall(MatDestroy(&intMat2));
2398           PetscCall(PetscQuadratureDestroy(&intNodes));
2399           PetscCall(PetscQuadratureDestroy(&intNodes2));
2400           PetscCall(PetscLagNodeIndicesDestroy(&intNodeIndices));
2401           PetscCall(PetscLagNodeIndicesDestroy(&intNodeIndices2));
2402           intNodes       = merged;
2403           intMat         = matMerged;
2404           intNodeIndices = intNodeIndicesMerged;
2405           if (!trimmed) {
2406             /* I think users expect that, when a node has a full basis for the k-forms,
2407              * they should be consecutive dofs.  That isn't the case for trimmed spaces,
2408              * but is for some of the nodes in untrimmed spaces, so in that case we
2409              * sort them to group them by node */
2410             Mat intMatPerm;
2411 
2412             PetscCall(MatPermuteByNodeIdx(intMat, intNodeIndices, &intMatPerm));
2413             PetscCall(MatDestroy(&intMat));
2414             intMat = intMatPerm;
2415           }
2416         }
2417       }
2418       PetscCall(PetscDualSpaceDestroy(&fiber));
2419       PetscCall(PetscDualSpaceDestroy(&trace));
2420     }
2421     PetscCall(PetscQuadratureDestroy(&intNodesTrace));
2422     PetscCall(PetscQuadratureDestroy(&intNodesFiber));
2423     sp->intNodes        = intNodes;
2424     sp->intMat          = intMat;
2425     lag->intNodeIndices = intNodeIndices;
2426     {
2427       PetscInt nDofs = 0;
2428 
2429       if (intMat) PetscCall(MatGetSize(intMat, &nDofs, NULL));
2430       PetscCall(PetscSectionSetDof(section, 0, nDofs));
2431     }
2432     PetscCall(PetscDualSpaceSectionSetUp_Internal(sp, section));
2433     if (continuous) {
2434       PetscCall(PetscDualSpaceCreateAllDataFromInteriorData(sp));
2435       PetscCall(PetscDualSpaceLagrangeCreateAllNodeIdx(sp));
2436     } else {
2437       PetscCall(PetscObjectReference((PetscObject)intNodes));
2438       sp->allNodes = intNodes;
2439       PetscCall(PetscObjectReference((PetscObject)intMat));
2440       sp->allMat = intMat;
2441       PetscCall(PetscLagNodeIndicesReference(intNodeIndices));
2442       lag->allNodeIndices = intNodeIndices;
2443     }
2444   }
2445   PetscCall(PetscSectionGetStorageSize(section, &sp->spdim));
2446   PetscCall(PetscSectionGetConstrainedStorageSize(section, &sp->spintdim));
2447   // TODO: fix this, computing functionals from moments should be no different for nodal vs modal
2448   if (lag->useMoments) {
2449     PetscCall(PetscDualSpaceComputeFunctionalsFromAllData_Moments(sp));
2450   } else {
2451     PetscCall(PetscDualSpaceComputeFunctionalsFromAllData(sp));
2452   }
2453   PetscCall(PetscFree2(pStratStart, pStratEnd));
2454   PetscCall(DMDestroy(&dmint));
2455   PetscFunctionReturn(PETSC_SUCCESS);
2456 }
2457 
2458 /* Create a matrix that represents the transformation that DMPlexVecGetClosure() would need
2459  * to get the representation of the dofs for a mesh point if the mesh point had this orientation
2460  * relative to the cell */
2461 PetscErrorCode PetscDualSpaceCreateInteriorSymmetryMatrix_Lagrange(PetscDualSpace sp, PetscInt ornt, Mat *symMat)
2462 {
2463   PetscDualSpace_Lag *lag;
2464   DM                  dm;
2465   PetscLagNodeIndices vertIndices, intNodeIndices;
2466   PetscLagNodeIndices ni;
2467   PetscInt            nodeIdxDim, nodeVecDim, nNodes;
2468   PetscInt            formDegree;
2469   PetscInt           *perm, *permOrnt;
2470   PetscInt           *nnz;
2471   PetscInt            n;
2472   PetscInt            maxGroupSize;
2473   PetscScalar        *V, *W, *work;
2474   Mat                 A;
2475 
2476   PetscFunctionBegin;
2477   if (!sp->spintdim) {
2478     *symMat = NULL;
2479     PetscFunctionReturn(PETSC_SUCCESS);
2480   }
2481   lag            = (PetscDualSpace_Lag *)sp->data;
2482   vertIndices    = lag->vertIndices;
2483   intNodeIndices = lag->intNodeIndices;
2484   PetscCall(PetscDualSpaceGetDM(sp, &dm));
2485   PetscCall(PetscDualSpaceGetFormDegree(sp, &formDegree));
2486   PetscCall(PetscNew(&ni));
2487   ni->refct      = 1;
2488   ni->nodeIdxDim = nodeIdxDim = intNodeIndices->nodeIdxDim;
2489   ni->nodeVecDim = nodeVecDim = intNodeIndices->nodeVecDim;
2490   ni->nNodes = nNodes = intNodeIndices->nNodes;
2491   PetscCall(PetscMalloc1(nNodes * nodeIdxDim, &ni->nodeIdx));
2492   PetscCall(PetscMalloc1(nNodes * nodeVecDim, &ni->nodeVec));
2493   /* push forward the dofs by the symmetry of the reference element induced by ornt */
2494   PetscCall(PetscLagNodeIndicesPushForward(dm, vertIndices, 0, vertIndices, intNodeIndices, ornt, formDegree, ni->nodeIdx, ni->nodeVec));
2495   /* get the revlex order for both the original and transformed dofs */
2496   PetscCall(PetscLagNodeIndicesGetPermutation(intNodeIndices, &perm));
2497   PetscCall(PetscLagNodeIndicesGetPermutation(ni, &permOrnt));
2498   PetscCall(PetscMalloc1(nNodes, &nnz));
2499   for (n = 0, maxGroupSize = 0; n < nNodes;) { /* incremented in the loop */
2500     PetscInt *nind = &(ni->nodeIdx[permOrnt[n] * nodeIdxDim]);
2501     PetscInt  m, nEnd;
2502     PetscInt  groupSize;
2503     /* for each group of dofs that have the same nodeIdx coordinate */
2504     for (nEnd = n + 1; nEnd < nNodes; nEnd++) {
2505       PetscInt *mind = &(ni->nodeIdx[permOrnt[nEnd] * nodeIdxDim]);
2506       PetscInt  d;
2507 
2508       /* compare the oriented permutation indices */
2509       for (d = 0; d < nodeIdxDim; d++)
2510         if (mind[d] != nind[d]) break;
2511       if (d < nodeIdxDim) break;
2512     }
2513     /* permOrnt[[n, nEnd)] is a group of dofs that, under the symmetry are at the same location */
2514 
2515     /* the symmetry had better map the group of dofs with the same permuted nodeIdx
2516      * to a group of dofs with the same size, otherwise we messed up */
2517     if (PetscDefined(USE_DEBUG)) {
2518       PetscInt  m;
2519       PetscInt *nind = &(intNodeIndices->nodeIdx[perm[n] * nodeIdxDim]);
2520 
2521       for (m = n + 1; m < nEnd; m++) {
2522         PetscInt *mind = &(intNodeIndices->nodeIdx[perm[m] * nodeIdxDim]);
2523         PetscInt  d;
2524 
2525         /* compare the oriented permutation indices */
2526         for (d = 0; d < nodeIdxDim; d++)
2527           if (mind[d] != nind[d]) break;
2528         if (d < nodeIdxDim) break;
2529       }
2530       PetscCheck(m >= nEnd, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Dofs with same index after symmetry not same block size");
2531     }
2532     groupSize = nEnd - n;
2533     /* each pushforward dof vector will be expressed in a basis of the unpermuted dofs */
2534     for (m = n; m < nEnd; m++) nnz[permOrnt[m]] = groupSize;
2535 
2536     maxGroupSize = PetscMax(maxGroupSize, nEnd - n);
2537     n            = nEnd;
2538   }
2539   PetscCheck(maxGroupSize <= nodeVecDim, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Dofs are not in blocks that can be solved");
2540   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, nNodes, nNodes, 0, nnz, &A));
2541   PetscCall(PetscObjectSetOptionsPrefix((PetscObject)A, "lag_"));
2542   PetscCall(PetscFree(nnz));
2543   PetscCall(PetscMalloc3(maxGroupSize * nodeVecDim, &V, maxGroupSize * nodeVecDim, &W, nodeVecDim * 2, &work));
2544   for (n = 0; n < nNodes;) { /* incremented in the loop */
2545     PetscInt *nind = &(ni->nodeIdx[permOrnt[n] * nodeIdxDim]);
2546     PetscInt  nEnd;
2547     PetscInt  m;
2548     PetscInt  groupSize;
2549     for (nEnd = n + 1; nEnd < nNodes; nEnd++) {
2550       PetscInt *mind = &(ni->nodeIdx[permOrnt[nEnd] * nodeIdxDim]);
2551       PetscInt  d;
2552 
2553       /* compare the oriented permutation indices */
2554       for (d = 0; d < nodeIdxDim; d++)
2555         if (mind[d] != nind[d]) break;
2556       if (d < nodeIdxDim) break;
2557     }
2558     groupSize = nEnd - n;
2559     /* get all of the vectors from the original and all of the pushforward vectors */
2560     for (m = n; m < nEnd; m++) {
2561       PetscInt d;
2562 
2563       for (d = 0; d < nodeVecDim; d++) {
2564         V[(m - n) * nodeVecDim + d] = intNodeIndices->nodeVec[perm[m] * nodeVecDim + d];
2565         W[(m - n) * nodeVecDim + d] = ni->nodeVec[permOrnt[m] * nodeVecDim + d];
2566       }
2567     }
2568     /* now we have to solve for W in terms of V: the systems isn't always square, but the span
2569      * of V and W should always be the same, so the solution of the normal equations works */
2570     {
2571       char         transpose = 'N';
2572       PetscBLASInt bm, bn, bnrhs, blda, bldb, blwork, info;
2573 
2574       PetscCall(PetscBLASIntCast(nodeVecDim, &bm));
2575       PetscCall(PetscBLASIntCast(groupSize, &bn));
2576       PetscCall(PetscBLASIntCast(groupSize, &bnrhs));
2577       PetscCall(PetscBLASIntCast(bm, &blda));
2578       PetscCall(PetscBLASIntCast(bm, &bldb));
2579       PetscCall(PetscBLASIntCast(2 * nodeVecDim, &blwork));
2580       PetscCallBLAS("LAPACKgels", LAPACKgels_(&transpose, &bm, &bn, &bnrhs, V, &blda, W, &bldb, work, &blwork, &info));
2581       PetscCheck(info == 0, PETSC_COMM_SELF, PETSC_ERR_LIB, "Bad argument to GELS");
2582       /* repack */
2583       {
2584         PetscInt i, j;
2585 
2586         for (i = 0; i < groupSize; i++) {
2587           for (j = 0; j < groupSize; j++) {
2588             /* notice the different leading dimension */
2589             V[i * groupSize + j] = W[i * nodeVecDim + j];
2590           }
2591         }
2592       }
2593       if (PetscDefined(USE_DEBUG)) {
2594         PetscReal res;
2595 
2596         /* check that the normal error is 0 */
2597         for (m = n; m < nEnd; m++) {
2598           PetscInt d;
2599 
2600           for (d = 0; d < nodeVecDim; d++) W[(m - n) * nodeVecDim + d] = ni->nodeVec[permOrnt[m] * nodeVecDim + d];
2601         }
2602         res = 0.;
2603         for (PetscInt i = 0; i < groupSize; i++) {
2604           for (PetscInt j = 0; j < nodeVecDim; j++) {
2605             for (PetscInt k = 0; k < groupSize; k++) W[i * nodeVecDim + j] -= V[i * groupSize + k] * intNodeIndices->nodeVec[perm[n + k] * nodeVecDim + j];
2606             res += PetscAbsScalar(W[i * nodeVecDim + j]);
2607           }
2608         }
2609         PetscCheck(res <= PETSC_SMALL, PETSC_COMM_SELF, PETSC_ERR_LIB, "Dof block did not solve");
2610       }
2611     }
2612     PetscCall(MatSetValues(A, groupSize, &permOrnt[n], groupSize, &perm[n], V, INSERT_VALUES));
2613     n = nEnd;
2614   }
2615   PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
2616   PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));
2617   *symMat = A;
2618   PetscCall(PetscFree3(V, W, work));
2619   PetscCall(PetscLagNodeIndicesDestroy(&ni));
2620   PetscFunctionReturn(PETSC_SUCCESS);
2621 }
2622 
2623 // get the symmetries of closure points
2624 PETSC_INTERN PetscErrorCode PetscDualSpaceGetBoundarySymmetries_Internal(PetscDualSpace sp, PetscInt ***symperms, PetscScalar ***symflips)
2625 {
2626   PetscInt  closureSize = 0;
2627   PetscInt *closure     = NULL;
2628   PetscInt  r;
2629 
2630   PetscFunctionBegin;
2631   PetscCall(DMPlexGetTransitiveClosure(sp->dm, 0, PETSC_TRUE, &closureSize, &closure));
2632   for (r = 0; r < closureSize; r++) {
2633     PetscDualSpace       psp;
2634     PetscInt             point = closure[2 * r];
2635     PetscInt             pspintdim;
2636     const PetscInt    ***psymperms = NULL;
2637     const PetscScalar ***psymflips = NULL;
2638 
2639     if (!point) continue;
2640     PetscCall(PetscDualSpaceGetPointSubspace(sp, point, &psp));
2641     if (!psp) continue;
2642     PetscCall(PetscDualSpaceGetInteriorDimension(psp, &pspintdim));
2643     if (!pspintdim) continue;
2644     PetscCall(PetscDualSpaceGetSymmetries(psp, &psymperms, &psymflips));
2645     symperms[r] = (PetscInt **)(psymperms ? psymperms[0] : NULL);
2646     symflips[r] = (PetscScalar **)(psymflips ? psymflips[0] : NULL);
2647   }
2648   PetscCall(DMPlexRestoreTransitiveClosure(sp->dm, 0, PETSC_TRUE, &closureSize, &closure));
2649   PetscFunctionReturn(PETSC_SUCCESS);
2650 }
2651 
2652 #define BaryIndex(perEdge, a, b, c) (((b) * (2 * perEdge + 1 - (b))) / 2) + (c)
2653 
2654 #define CartIndex(perEdge, a, b) (perEdge * (a) + b)
2655 
2656 /* the existing interface for symmetries is insufficient for all cases:
2657  * - it should be sufficient for form degrees that are scalar (0 and n)
2658  * - it should be sufficient for hypercube dofs
2659  * - it isn't sufficient for simplex cells with non-scalar form degrees if
2660  *   there are any dofs in the interior
2661  *
2662  * We compute the general transformation matrices, and if they fit, we return them,
2663  * otherwise we error (but we should probably change the interface to allow for
2664  * these symmetries)
2665  */
2666 static PetscErrorCode PetscDualSpaceGetSymmetries_Lagrange(PetscDualSpace sp, const PetscInt ****perms, const PetscScalar ****flips)
2667 {
2668   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2669   PetscInt            dim, order, Nc;
2670 
2671   PetscFunctionBegin;
2672   PetscCall(PetscDualSpaceGetOrder(sp, &order));
2673   PetscCall(PetscDualSpaceGetNumComponents(sp, &Nc));
2674   PetscCall(DMGetDimension(sp->dm, &dim));
2675   if (!lag->symComputed) { /* store symmetries */
2676     PetscInt       pStart, pEnd, p;
2677     PetscInt       numPoints;
2678     PetscInt       numFaces;
2679     PetscInt       spintdim;
2680     PetscInt    ***symperms;
2681     PetscScalar ***symflips;
2682 
2683     PetscCall(DMPlexGetChart(sp->dm, &pStart, &pEnd));
2684     numPoints = pEnd - pStart;
2685     {
2686       DMPolytopeType ct;
2687       /* The number of arrangements is no longer based on the number of faces */
2688       PetscCall(DMPlexGetCellType(sp->dm, 0, &ct));
2689       numFaces = DMPolytopeTypeGetNumArrangements(ct) / 2;
2690     }
2691     PetscCall(PetscCalloc1(numPoints, &symperms));
2692     PetscCall(PetscCalloc1(numPoints, &symflips));
2693     spintdim = sp->spintdim;
2694     /* The nodal symmetry behavior is not present when tensorSpace != tensorCell: someone might want this for the "S"
2695      * family of FEEC spaces.  Most used in particular are discontinuous polynomial L2 spaces in tensor cells, where
2696      * the symmetries are not necessary for FE assembly.  So for now we assume this is the case and don't return
2697      * symmetries if tensorSpace != tensorCell */
2698     if (spintdim && 0 < dim && dim < 3 && (lag->tensorSpace == lag->tensorCell)) { /* compute self symmetries */
2699       PetscInt    **cellSymperms;
2700       PetscScalar **cellSymflips;
2701       PetscInt      ornt;
2702       PetscInt      nCopies = Nc / lag->intNodeIndices->nodeVecDim;
2703       PetscInt      nNodes  = lag->intNodeIndices->nNodes;
2704 
2705       lag->numSelfSym = 2 * numFaces;
2706       lag->selfSymOff = numFaces;
2707       PetscCall(PetscCalloc1(2 * numFaces, &cellSymperms));
2708       PetscCall(PetscCalloc1(2 * numFaces, &cellSymflips));
2709       /* we want to be able to index symmetries directly with the orientations, which range from [-numFaces,numFaces) */
2710       symperms[0] = &cellSymperms[numFaces];
2711       symflips[0] = &cellSymflips[numFaces];
2712       PetscCheck(lag->intNodeIndices->nodeVecDim * nCopies == Nc, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Node indices incompatible with dofs");
2713       PetscCheck(nNodes * nCopies == spintdim, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Node indices incompatible with dofs");
2714       for (ornt = -numFaces; ornt < numFaces; ornt++) { /* for every symmetry, compute the symmetry matrix, and extract rows to see if it fits in the perm + flip framework */
2715         Mat          symMat;
2716         PetscInt    *perm;
2717         PetscScalar *flips;
2718         PetscInt     i;
2719 
2720         if (!ornt) continue;
2721         PetscCall(PetscMalloc1(spintdim, &perm));
2722         PetscCall(PetscCalloc1(spintdim, &flips));
2723         for (i = 0; i < spintdim; i++) perm[i] = -1;
2724         PetscCall(PetscDualSpaceCreateInteriorSymmetryMatrix_Lagrange(sp, ornt, &symMat));
2725         for (i = 0; i < nNodes; i++) {
2726           PetscInt           ncols;
2727           PetscInt           j, k;
2728           const PetscInt    *cols;
2729           const PetscScalar *vals;
2730           PetscBool          nz_seen = PETSC_FALSE;
2731 
2732           PetscCall(MatGetRow(symMat, i, &ncols, &cols, &vals));
2733           for (j = 0; j < ncols; j++) {
2734             if (PetscAbsScalar(vals[j]) > PETSC_SMALL) {
2735               PetscCheck(!nz_seen, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "This dual space has symmetries that can't be described as a permutation + sign flips");
2736               nz_seen = PETSC_TRUE;
2737               PetscCheck(PetscAbsReal(PetscAbsScalar(vals[j]) - PetscRealConstant(1.)) <= PETSC_SMALL, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "This dual space has symmetries that can't be described as a permutation + sign flips");
2738               PetscCheck(PetscAbsReal(PetscImaginaryPart(vals[j])) <= PETSC_SMALL, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "This dual space has symmetries that can't be described as a permutation + sign flips");
2739               PetscCheck(perm[cols[j] * nCopies] < 0, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "This dual space has symmetries that can't be described as a permutation + sign flips");
2740               for (k = 0; k < nCopies; k++) perm[cols[j] * nCopies + k] = i * nCopies + k;
2741               if (PetscRealPart(vals[j]) < 0.) {
2742                 for (k = 0; k < nCopies; k++) flips[i * nCopies + k] = -1.;
2743               } else {
2744                 for (k = 0; k < nCopies; k++) flips[i * nCopies + k] = 1.;
2745               }
2746             }
2747           }
2748           PetscCall(MatRestoreRow(symMat, i, &ncols, &cols, &vals));
2749         }
2750         PetscCall(MatDestroy(&symMat));
2751         /* if there were no sign flips, keep NULL */
2752         for (i = 0; i < spintdim; i++)
2753           if (flips[i] != 1.) break;
2754         if (i == spintdim) {
2755           PetscCall(PetscFree(flips));
2756           flips = NULL;
2757         }
2758         /* if the permutation is identity, keep NULL */
2759         for (i = 0; i < spintdim; i++)
2760           if (perm[i] != i) break;
2761         if (i == spintdim) {
2762           PetscCall(PetscFree(perm));
2763           perm = NULL;
2764         }
2765         symperms[0][ornt] = perm;
2766         symflips[0][ornt] = flips;
2767       }
2768       /* if no orientations produced non-identity permutations, keep NULL */
2769       for (ornt = -numFaces; ornt < numFaces; ornt++)
2770         if (symperms[0][ornt]) break;
2771       if (ornt == numFaces) {
2772         PetscCall(PetscFree(cellSymperms));
2773         symperms[0] = NULL;
2774       }
2775       /* if no orientations produced sign flips, keep NULL */
2776       for (ornt = -numFaces; ornt < numFaces; ornt++)
2777         if (symflips[0][ornt]) break;
2778       if (ornt == numFaces) {
2779         PetscCall(PetscFree(cellSymflips));
2780         symflips[0] = NULL;
2781       }
2782     }
2783     PetscCall(PetscDualSpaceGetBoundarySymmetries_Internal(sp, symperms, symflips));
2784     for (p = 0; p < pEnd; p++)
2785       if (symperms[p]) break;
2786     if (p == pEnd) {
2787       PetscCall(PetscFree(symperms));
2788       symperms = NULL;
2789     }
2790     for (p = 0; p < pEnd; p++)
2791       if (symflips[p]) break;
2792     if (p == pEnd) {
2793       PetscCall(PetscFree(symflips));
2794       symflips = NULL;
2795     }
2796     lag->symperms    = symperms;
2797     lag->symflips    = symflips;
2798     lag->symComputed = PETSC_TRUE;
2799   }
2800   if (perms) *perms = (const PetscInt ***)lag->symperms;
2801   if (flips) *flips = (const PetscScalar ***)lag->symflips;
2802   PetscFunctionReturn(PETSC_SUCCESS);
2803 }
2804 
2805 static PetscErrorCode PetscDualSpaceLagrangeGetContinuity_Lagrange(PetscDualSpace sp, PetscBool *continuous)
2806 {
2807   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2808 
2809   PetscFunctionBegin;
2810   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
2811   PetscAssertPointer(continuous, 2);
2812   *continuous = lag->continuous;
2813   PetscFunctionReturn(PETSC_SUCCESS);
2814 }
2815 
2816 static PetscErrorCode PetscDualSpaceLagrangeSetContinuity_Lagrange(PetscDualSpace sp, PetscBool continuous)
2817 {
2818   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2819 
2820   PetscFunctionBegin;
2821   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
2822   lag->continuous = continuous;
2823   PetscFunctionReturn(PETSC_SUCCESS);
2824 }
2825 
2826 /*@
2827   PetscDualSpaceLagrangeGetContinuity - Retrieves the flag for element continuity
2828 
2829   Not Collective
2830 
2831   Input Parameter:
2832 . sp - the `PetscDualSpace`
2833 
2834   Output Parameter:
2835 . continuous - flag for element continuity
2836 
2837   Level: intermediate
2838 
2839 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDualSpaceLagrangeSetContinuity()`
2840 @*/
2841 PetscErrorCode PetscDualSpaceLagrangeGetContinuity(PetscDualSpace sp, PetscBool *continuous)
2842 {
2843   PetscFunctionBegin;
2844   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
2845   PetscAssertPointer(continuous, 2);
2846   PetscTryMethod(sp, "PetscDualSpaceLagrangeGetContinuity_C", (PetscDualSpace, PetscBool *), (sp, continuous));
2847   PetscFunctionReturn(PETSC_SUCCESS);
2848 }
2849 
2850 /*@
2851   PetscDualSpaceLagrangeSetContinuity - Indicate whether the element is continuous
2852 
2853   Logically Collective
2854 
2855   Input Parameters:
2856 + sp         - the `PetscDualSpace`
2857 - continuous - flag for element continuity
2858 
2859   Options Database Key:
2860 . -petscdualspace_lagrange_continuity <bool> - use a continuous element
2861 
2862   Level: intermediate
2863 
2864 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDualSpaceLagrangeGetContinuity()`
2865 @*/
2866 PetscErrorCode PetscDualSpaceLagrangeSetContinuity(PetscDualSpace sp, PetscBool continuous)
2867 {
2868   PetscFunctionBegin;
2869   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
2870   PetscValidLogicalCollectiveBool(sp, continuous, 2);
2871   PetscTryMethod(sp, "PetscDualSpaceLagrangeSetContinuity_C", (PetscDualSpace, PetscBool), (sp, continuous));
2872   PetscFunctionReturn(PETSC_SUCCESS);
2873 }
2874 
2875 static PetscErrorCode PetscDualSpaceLagrangeGetTensor_Lagrange(PetscDualSpace sp, PetscBool *tensor)
2876 {
2877   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2878 
2879   PetscFunctionBegin;
2880   *tensor = lag->tensorSpace;
2881   PetscFunctionReturn(PETSC_SUCCESS);
2882 }
2883 
2884 static PetscErrorCode PetscDualSpaceLagrangeSetTensor_Lagrange(PetscDualSpace sp, PetscBool tensor)
2885 {
2886   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2887 
2888   PetscFunctionBegin;
2889   lag->tensorSpace = tensor;
2890   PetscFunctionReturn(PETSC_SUCCESS);
2891 }
2892 
2893 static PetscErrorCode PetscDualSpaceLagrangeGetTrimmed_Lagrange(PetscDualSpace sp, PetscBool *trimmed)
2894 {
2895   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2896 
2897   PetscFunctionBegin;
2898   *trimmed = lag->trimmed;
2899   PetscFunctionReturn(PETSC_SUCCESS);
2900 }
2901 
2902 static PetscErrorCode PetscDualSpaceLagrangeSetTrimmed_Lagrange(PetscDualSpace sp, PetscBool trimmed)
2903 {
2904   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2905 
2906   PetscFunctionBegin;
2907   lag->trimmed = trimmed;
2908   PetscFunctionReturn(PETSC_SUCCESS);
2909 }
2910 
2911 static PetscErrorCode PetscDualSpaceLagrangeGetNodeType_Lagrange(PetscDualSpace sp, PetscDTNodeType *nodeType, PetscBool *boundary, PetscReal *exponent)
2912 {
2913   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2914 
2915   PetscFunctionBegin;
2916   if (nodeType) *nodeType = lag->nodeType;
2917   if (boundary) *boundary = lag->endNodes;
2918   if (exponent) *exponent = lag->nodeExponent;
2919   PetscFunctionReturn(PETSC_SUCCESS);
2920 }
2921 
2922 static PetscErrorCode PetscDualSpaceLagrangeSetNodeType_Lagrange(PetscDualSpace sp, PetscDTNodeType nodeType, PetscBool boundary, PetscReal exponent)
2923 {
2924   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2925 
2926   PetscFunctionBegin;
2927   PetscCheck(nodeType != PETSCDTNODES_GAUSSJACOBI || exponent > -1., PetscObjectComm((PetscObject)sp), PETSC_ERR_ARG_OUTOFRANGE, "Exponent must be > -1");
2928   lag->nodeType     = nodeType;
2929   lag->endNodes     = boundary;
2930   lag->nodeExponent = exponent;
2931   PetscFunctionReturn(PETSC_SUCCESS);
2932 }
2933 
2934 static PetscErrorCode PetscDualSpaceLagrangeGetUseMoments_Lagrange(PetscDualSpace sp, PetscBool *useMoments)
2935 {
2936   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2937 
2938   PetscFunctionBegin;
2939   *useMoments = lag->useMoments;
2940   PetscFunctionReturn(PETSC_SUCCESS);
2941 }
2942 
2943 static PetscErrorCode PetscDualSpaceLagrangeSetUseMoments_Lagrange(PetscDualSpace sp, PetscBool useMoments)
2944 {
2945   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2946 
2947   PetscFunctionBegin;
2948   lag->useMoments = useMoments;
2949   PetscFunctionReturn(PETSC_SUCCESS);
2950 }
2951 
2952 static PetscErrorCode PetscDualSpaceLagrangeGetMomentOrder_Lagrange(PetscDualSpace sp, PetscInt *momentOrder)
2953 {
2954   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2955 
2956   PetscFunctionBegin;
2957   *momentOrder = lag->momentOrder;
2958   PetscFunctionReturn(PETSC_SUCCESS);
2959 }
2960 
2961 static PetscErrorCode PetscDualSpaceLagrangeSetMomentOrder_Lagrange(PetscDualSpace sp, PetscInt momentOrder)
2962 {
2963   PetscDualSpace_Lag *lag = (PetscDualSpace_Lag *)sp->data;
2964 
2965   PetscFunctionBegin;
2966   lag->momentOrder = momentOrder;
2967   PetscFunctionReturn(PETSC_SUCCESS);
2968 }
2969 
2970 /*@
2971   PetscDualSpaceLagrangeGetTensor - Get the tensor nature of the dual space
2972 
2973   Not Collective
2974 
2975   Input Parameter:
2976 . sp - The `PetscDualSpace`
2977 
2978   Output Parameter:
2979 . tensor - Whether the dual space has tensor layout (vs. simplicial)
2980 
2981   Level: intermediate
2982 
2983 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDualSpaceLagrangeSetTensor()`, `PetscDualSpaceCreate()`
2984 @*/
2985 PetscErrorCode PetscDualSpaceLagrangeGetTensor(PetscDualSpace sp, PetscBool *tensor)
2986 {
2987   PetscFunctionBegin;
2988   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
2989   PetscAssertPointer(tensor, 2);
2990   PetscTryMethod(sp, "PetscDualSpaceLagrangeGetTensor_C", (PetscDualSpace, PetscBool *), (sp, tensor));
2991   PetscFunctionReturn(PETSC_SUCCESS);
2992 }
2993 
2994 /*@
2995   PetscDualSpaceLagrangeSetTensor - Set the tensor nature of the dual space
2996 
2997   Not Collective
2998 
2999   Input Parameters:
3000 + sp     - The `PetscDualSpace`
3001 - tensor - Whether the dual space has tensor layout (vs. simplicial)
3002 
3003   Level: intermediate
3004 
3005 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDualSpaceLagrangeGetTensor()`, `PetscDualSpaceCreate()`
3006 @*/
3007 PetscErrorCode PetscDualSpaceLagrangeSetTensor(PetscDualSpace sp, PetscBool tensor)
3008 {
3009   PetscFunctionBegin;
3010   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
3011   PetscTryMethod(sp, "PetscDualSpaceLagrangeSetTensor_C", (PetscDualSpace, PetscBool), (sp, tensor));
3012   PetscFunctionReturn(PETSC_SUCCESS);
3013 }
3014 
3015 /*@
3016   PetscDualSpaceLagrangeGetTrimmed - Get the trimmed nature of the dual space
3017 
3018   Not Collective
3019 
3020   Input Parameter:
3021 . sp - The `PetscDualSpace`
3022 
3023   Output Parameter:
3024 . trimmed - Whether the dual space represents to dual basis of a trimmed polynomial space (e.g. Raviart-Thomas and higher order / other form degree variants)
3025 
3026   Level: intermediate
3027 
3028 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDualSpaceLagrangeSetTrimmed()`, `PetscDualSpaceCreate()`
3029 @*/
3030 PetscErrorCode PetscDualSpaceLagrangeGetTrimmed(PetscDualSpace sp, PetscBool *trimmed)
3031 {
3032   PetscFunctionBegin;
3033   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
3034   PetscAssertPointer(trimmed, 2);
3035   PetscTryMethod(sp, "PetscDualSpaceLagrangeGetTrimmed_C", (PetscDualSpace, PetscBool *), (sp, trimmed));
3036   PetscFunctionReturn(PETSC_SUCCESS);
3037 }
3038 
3039 /*@
3040   PetscDualSpaceLagrangeSetTrimmed - Set the trimmed nature of the dual space
3041 
3042   Not Collective
3043 
3044   Input Parameters:
3045 + sp      - The `PetscDualSpace`
3046 - trimmed - Whether the dual space represents to dual basis of a trimmed polynomial space (e.g. Raviart-Thomas and higher order / other form degree variants)
3047 
3048   Level: intermediate
3049 
3050 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDualSpaceLagrangeGetTrimmed()`, `PetscDualSpaceCreate()`
3051 @*/
3052 PetscErrorCode PetscDualSpaceLagrangeSetTrimmed(PetscDualSpace sp, PetscBool trimmed)
3053 {
3054   PetscFunctionBegin;
3055   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
3056   PetscTryMethod(sp, "PetscDualSpaceLagrangeSetTrimmed_C", (PetscDualSpace, PetscBool), (sp, trimmed));
3057   PetscFunctionReturn(PETSC_SUCCESS);
3058 }
3059 
3060 /*@
3061   PetscDualSpaceLagrangeGetNodeType - Get a description of how nodes are laid out for Lagrange polynomials in this
3062   dual space
3063 
3064   Not Collective
3065 
3066   Input Parameter:
3067 . sp - The `PetscDualSpace`
3068 
3069   Output Parameters:
3070 + nodeType - The type of nodes
3071 . boundary - Whether the node type is one that includes endpoints (if nodeType is `PETSCDTNODES_GAUSSJACOBI`, nodes that
3072              include the boundary are Gauss-Lobatto-Jacobi nodes)
3073 - exponent - If nodeType is `PETSCDTNODES_GAUSJACOBI`, indicates the exponent used for both ends of the 1D Jacobi weight function
3074              '0' is Gauss-Legendre, '-0.5' is Gauss-Chebyshev of the first type, '0.5' is Gauss-Chebyshev of the second type
3075 
3076   Level: advanced
3077 
3078 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDTNodeType`, `PetscDualSpaceLagrangeSetNodeType()`
3079 @*/
3080 PetscErrorCode PetscDualSpaceLagrangeGetNodeType(PetscDualSpace sp, PetscDTNodeType *nodeType, PetscBool *boundary, PetscReal *exponent)
3081 {
3082   PetscFunctionBegin;
3083   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
3084   if (nodeType) PetscAssertPointer(nodeType, 2);
3085   if (boundary) PetscAssertPointer(boundary, 3);
3086   if (exponent) PetscAssertPointer(exponent, 4);
3087   PetscTryMethod(sp, "PetscDualSpaceLagrangeGetNodeType_C", (PetscDualSpace, PetscDTNodeType *, PetscBool *, PetscReal *), (sp, nodeType, boundary, exponent));
3088   PetscFunctionReturn(PETSC_SUCCESS);
3089 }
3090 
3091 /*@
3092   PetscDualSpaceLagrangeSetNodeType - Set a description of how nodes are laid out for Lagrange polynomials in this
3093   dual space
3094 
3095   Logically Collective
3096 
3097   Input Parameters:
3098 + sp       - The `PetscDualSpace`
3099 . nodeType - The type of nodes
3100 . boundary - Whether the node type is one that includes endpoints (if nodeType is `PETSCDTNODES_GAUSSJACOBI`, nodes that
3101              include the boundary are Gauss-Lobatto-Jacobi nodes)
3102 - exponent - If nodeType is `PETSCDTNODES_GAUSJACOBI`, indicates the exponent used for both ends of the 1D Jacobi weight function
3103              '0' is Gauss-Legendre, '-0.5' is Gauss-Chebyshev of the first type, '0.5' is Gauss-Chebyshev of the second type
3104 
3105   Level: advanced
3106 
3107 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDTNodeType`, `PetscDualSpaceLagrangeGetNodeType()`
3108 @*/
3109 PetscErrorCode PetscDualSpaceLagrangeSetNodeType(PetscDualSpace sp, PetscDTNodeType nodeType, PetscBool boundary, PetscReal exponent)
3110 {
3111   PetscFunctionBegin;
3112   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
3113   PetscTryMethod(sp, "PetscDualSpaceLagrangeSetNodeType_C", (PetscDualSpace, PetscDTNodeType, PetscBool, PetscReal), (sp, nodeType, boundary, exponent));
3114   PetscFunctionReturn(PETSC_SUCCESS);
3115 }
3116 
3117 /*@
3118   PetscDualSpaceLagrangeGetUseMoments - Get the flag for using moment functionals
3119 
3120   Not Collective
3121 
3122   Input Parameter:
3123 . sp - The `PetscDualSpace`
3124 
3125   Output Parameter:
3126 . useMoments - Moment flag
3127 
3128   Level: advanced
3129 
3130 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDualSpaceLagrangeSetUseMoments()`
3131 @*/
3132 PetscErrorCode PetscDualSpaceLagrangeGetUseMoments(PetscDualSpace sp, PetscBool *useMoments)
3133 {
3134   PetscFunctionBegin;
3135   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
3136   PetscAssertPointer(useMoments, 2);
3137   PetscUseMethod(sp, "PetscDualSpaceLagrangeGetUseMoments_C", (PetscDualSpace, PetscBool *), (sp, useMoments));
3138   PetscFunctionReturn(PETSC_SUCCESS);
3139 }
3140 
3141 /*@
3142   PetscDualSpaceLagrangeSetUseMoments - Set the flag for moment functionals
3143 
3144   Logically Collective
3145 
3146   Input Parameters:
3147 + sp         - The `PetscDualSpace`
3148 - useMoments - The flag for moment functionals
3149 
3150   Level: advanced
3151 
3152 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDualSpaceLagrangeGetUseMoments()`
3153 @*/
3154 PetscErrorCode PetscDualSpaceLagrangeSetUseMoments(PetscDualSpace sp, PetscBool useMoments)
3155 {
3156   PetscFunctionBegin;
3157   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
3158   PetscTryMethod(sp, "PetscDualSpaceLagrangeSetUseMoments_C", (PetscDualSpace, PetscBool), (sp, useMoments));
3159   PetscFunctionReturn(PETSC_SUCCESS);
3160 }
3161 
3162 /*@
3163   PetscDualSpaceLagrangeGetMomentOrder - Get the order for moment integration
3164 
3165   Not Collective
3166 
3167   Input Parameter:
3168 . sp - The `PetscDualSpace`
3169 
3170   Output Parameter:
3171 . order - Moment integration order
3172 
3173   Level: advanced
3174 
3175 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDualSpaceLagrangeSetMomentOrder()`
3176 @*/
3177 PetscErrorCode PetscDualSpaceLagrangeGetMomentOrder(PetscDualSpace sp, PetscInt *order)
3178 {
3179   PetscFunctionBegin;
3180   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
3181   PetscAssertPointer(order, 2);
3182   PetscUseMethod(sp, "PetscDualSpaceLagrangeGetMomentOrder_C", (PetscDualSpace, PetscInt *), (sp, order));
3183   PetscFunctionReturn(PETSC_SUCCESS);
3184 }
3185 
3186 /*@
3187   PetscDualSpaceLagrangeSetMomentOrder - Set the order for moment integration
3188 
3189   Logically Collective
3190 
3191   Input Parameters:
3192 + sp    - The `PetscDualSpace`
3193 - order - The order for moment integration
3194 
3195   Level: advanced
3196 
3197 .seealso: `PETSCDUALSPACELAGRANGE`, `PetscDualSpace`, `PetscDualSpaceLagrangeGetMomentOrder()`
3198 @*/
3199 PetscErrorCode PetscDualSpaceLagrangeSetMomentOrder(PetscDualSpace sp, PetscInt order)
3200 {
3201   PetscFunctionBegin;
3202   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
3203   PetscTryMethod(sp, "PetscDualSpaceLagrangeSetMomentOrder_C", (PetscDualSpace, PetscInt), (sp, order));
3204   PetscFunctionReturn(PETSC_SUCCESS);
3205 }
3206 
3207 static PetscErrorCode PetscDualSpaceInitialize_Lagrange(PetscDualSpace sp)
3208 {
3209   PetscFunctionBegin;
3210   sp->ops->destroy              = PetscDualSpaceDestroy_Lagrange;
3211   sp->ops->view                 = PetscDualSpaceView_Lagrange;
3212   sp->ops->setfromoptions       = PetscDualSpaceSetFromOptions_Lagrange;
3213   sp->ops->duplicate            = PetscDualSpaceDuplicate_Lagrange;
3214   sp->ops->setup                = PetscDualSpaceSetUp_Lagrange;
3215   sp->ops->createheightsubspace = NULL;
3216   sp->ops->createpointsubspace  = NULL;
3217   sp->ops->getsymmetries        = PetscDualSpaceGetSymmetries_Lagrange;
3218   sp->ops->apply                = PetscDualSpaceApplyDefault;
3219   sp->ops->applyall             = PetscDualSpaceApplyAllDefault;
3220   sp->ops->applyint             = PetscDualSpaceApplyInteriorDefault;
3221   sp->ops->createalldata        = PetscDualSpaceCreateAllDataDefault;
3222   sp->ops->createintdata        = PetscDualSpaceCreateInteriorDataDefault;
3223   PetscFunctionReturn(PETSC_SUCCESS);
3224 }
3225 
3226 /*MC
3227   PETSCDUALSPACELAGRANGE = "lagrange" - A `PetscDualSpaceType` that encapsulates a dual space of pointwise evaluation functionals
3228 
3229   Level: intermediate
3230 
3231   Developer Note:
3232   This `PetscDualSpace` seems to manage directly trimmed and untrimmed polynomials as well as tensor and non-tensor polynomials while for `PetscSpace` there seems to
3233   be different `PetscSpaceType` for them.
3234 
3235 .seealso: `PetscDualSpace`, `PetscDualSpaceType`, `PetscDualSpaceCreate()`, `PetscDualSpaceSetType()`,
3236           `PetscDualSpaceLagrangeSetMomentOrder()`, `PetscDualSpaceLagrangeGetMomentOrder()`, `PetscDualSpaceLagrangeSetUseMoments()`, `PetscDualSpaceLagrangeGetUseMoments()`,
3237           `PetscDualSpaceLagrangeSetNodeType, PetscDualSpaceLagrangeGetNodeType, PetscDualSpaceLagrangeGetContinuity, PetscDualSpaceLagrangeSetContinuity,
3238           `PetscDualSpaceLagrangeGetTensor()`, `PetscDualSpaceLagrangeSetTensor()`, `PetscDualSpaceLagrangeGetTrimmed()`, `PetscDualSpaceLagrangeSetTrimmed()`
3239 M*/
3240 PETSC_EXTERN PetscErrorCode PetscDualSpaceCreate_Lagrange(PetscDualSpace sp)
3241 {
3242   PetscDualSpace_Lag *lag;
3243 
3244   PetscFunctionBegin;
3245   PetscValidHeaderSpecific(sp, PETSCDUALSPACE_CLASSID, 1);
3246   PetscCall(PetscNew(&lag));
3247   sp->data = lag;
3248 
3249   lag->tensorCell  = PETSC_FALSE;
3250   lag->tensorSpace = PETSC_FALSE;
3251   lag->continuous  = PETSC_TRUE;
3252   lag->numCopies   = PETSC_DEFAULT;
3253   lag->numNodeSkip = PETSC_DEFAULT;
3254   lag->nodeType    = PETSCDTNODES_DEFAULT;
3255   lag->useMoments  = PETSC_FALSE;
3256   lag->momentOrder = 0;
3257 
3258   PetscCall(PetscDualSpaceInitialize_Lagrange(sp));
3259   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetContinuity_C", PetscDualSpaceLagrangeGetContinuity_Lagrange));
3260   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetContinuity_C", PetscDualSpaceLagrangeSetContinuity_Lagrange));
3261   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetTensor_C", PetscDualSpaceLagrangeGetTensor_Lagrange));
3262   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetTensor_C", PetscDualSpaceLagrangeSetTensor_Lagrange));
3263   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetTrimmed_C", PetscDualSpaceLagrangeGetTrimmed_Lagrange));
3264   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetTrimmed_C", PetscDualSpaceLagrangeSetTrimmed_Lagrange));
3265   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetNodeType_C", PetscDualSpaceLagrangeGetNodeType_Lagrange));
3266   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetNodeType_C", PetscDualSpaceLagrangeSetNodeType_Lagrange));
3267   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetUseMoments_C", PetscDualSpaceLagrangeGetUseMoments_Lagrange));
3268   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetUseMoments_C", PetscDualSpaceLagrangeSetUseMoments_Lagrange));
3269   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeGetMomentOrder_C", PetscDualSpaceLagrangeGetMomentOrder_Lagrange));
3270   PetscCall(PetscObjectComposeFunction((PetscObject)sp, "PetscDualSpaceLagrangeSetMomentOrder_C", PetscDualSpaceLagrangeSetMomentOrder_Lagrange));
3271   PetscFunctionReturn(PETSC_SUCCESS);
3272 }
3273