xref: /petsc/include/petscdt.h (revision daa252a5865999f1c6bc8348e4bad0b69e52d518)
1 /*
2   Common tools for constructing discretizations
3 */
4 #pragma once
5 
6 #include <petscsys.h>
7 #include <petscdmtypes.h>
8 #include <petscistypes.h>
9 
10 /* MANSEC = DM */
11 /* SUBMANSEC = DT */
12 
13 PETSC_EXTERN PetscClassId PETSCQUADRATURE_CLASSID;
14 
15 /*S
16   PetscQuadrature - Quadrature rule for numerical integration.
17 
18   Level: beginner
19 
20 .seealso: `PetscQuadratureCreate()`, `PetscQuadratureDestroy()`
21 S*/
22 typedef struct _p_PetscQuadrature *PetscQuadrature;
23 
24 /*E
25   PetscGaussLobattoLegendreCreateType - algorithm used to compute the Gauss-Lobatto-Legendre nodes and weights
26 
27   Values:
28 +  `PETSCGAUSSLOBATTOLEGENDRE_VIA_LINEAR_ALGEBRA` - compute the nodes via linear algebra
29 -  `PETSCGAUSSLOBATTOLEGENDRE_VIA_NEWTON`         - compute the nodes by solving a nonlinear equation with Newton's method
30 
31   Level: intermediate
32 
33 .seealso: `PetscQuadrature`
34 E*/
35 typedef enum {
36   PETSCGAUSSLOBATTOLEGENDRE_VIA_LINEAR_ALGEBRA,
37   PETSCGAUSSLOBATTOLEGENDRE_VIA_NEWTON
38 } PetscGaussLobattoLegendreCreateType;
39 
40 /*E
41   PetscDTNodeType - A description of strategies for generating nodes (both
42   quadrature nodes and nodes for Lagrange polynomials)
43 
44   Values:
45 + `PETSCDTNODES_DEFAULT`     - Nodes chosen by PETSc
46 . `PETSCDTNODES_GAUSSJACOBI` - Nodes at either Gauss-Jacobi or Gauss-Lobatto-Jacobi quadrature points
47 . `PETSCDTNODES_EQUISPACED`  - Nodes equispaced either including the endpoints or excluding them
48 - `PETSCDTNODES_TANHSINH`    - Nodes at Tanh-Sinh quadrature points
49 
50   Level: intermediate
51 
52   Note:
53   A `PetscDTNodeType` can be paired with a `PetscBool` to indicate whether
54   the nodes include endpoints or not, and in the case of `PETSCDT_GAUSSJACOBI`
55   with exponents for the weight function.
56 
57 .seealso: `PetscQuadrature`
58 E*/
59 typedef enum {
60   PETSCDTNODES_DEFAULT     = -1,
61   PETSCDTNODES_GAUSSJACOBI = 0,
62   PETSCDTNODES_EQUISPACED  = 1,
63   PETSCDTNODES_TANHSINH    = 2
64 } PetscDTNodeType;
65 
66 PETSC_EXTERN const char *const *const PetscDTNodeTypes;
67 
68 /*E
69   PetscDTSimplexQuadratureType - A description of classes of quadrature rules for simplices
70 
71   Values:
72 +  `PETSCDTSIMPLEXQUAD_DEFAULT` - Quadrature rule chosen by PETSc
73 .  `PETSCDTSIMPLEXQUAD_CONIC`   - Quadrature rules constructed as
74                                   conically-warped tensor products of 1D
75                                   Gauss-Jacobi quadrature rules.  These are
76                                   explicitly computable in any dimension for any
77                                   degree, and the tensor-product structure can be
78                                   exploited by sum-factorization methods, but
79                                   they are not efficient in terms of nodes per
80                                   polynomial degree.
81 -  `PETSCDTSIMPLEXQUAD_MINSYM`  - Quadrature rules that are fully symmetric
82                                   (symmetries of the simplex preserve the nodes
83                                   and weights) with minimal (or near minimal)
84                                   number of nodes.  In dimensions higher than 1
85                                   these are not simple to compute, so lookup
86                                   tables are used.
87 
88   Level: intermediate
89 
90 .seealso: `PetscQuadrature`, `PetscDTSimplexQuadrature()`
91 E*/
92 typedef enum {
93   PETSCDTSIMPLEXQUAD_DEFAULT = -1,
94   PETSCDTSIMPLEXQUAD_CONIC   = 0,
95   PETSCDTSIMPLEXQUAD_MINSYM  = 1
96 } PetscDTSimplexQuadratureType;
97 
98 PETSC_EXTERN const char *const *const PetscDTSimplexQuadratureTypes;
99 
100 PETSC_EXTERN PetscErrorCode PetscQuadratureCreate(MPI_Comm, PetscQuadrature *);
101 PETSC_EXTERN PetscErrorCode PetscQuadratureDuplicate(PetscQuadrature, PetscQuadrature *);
102 PETSC_EXTERN PetscErrorCode PetscQuadratureGetCellType(PetscQuadrature, DMPolytopeType *);
103 PETSC_EXTERN PetscErrorCode PetscQuadratureSetCellType(PetscQuadrature, DMPolytopeType);
104 PETSC_EXTERN PetscErrorCode PetscQuadratureGetOrder(PetscQuadrature, PetscInt *);
105 PETSC_EXTERN PetscErrorCode PetscQuadratureSetOrder(PetscQuadrature, PetscInt);
106 PETSC_EXTERN PetscErrorCode PetscQuadratureGetNumComponents(PetscQuadrature, PetscInt *);
107 PETSC_EXTERN PetscErrorCode PetscQuadratureSetNumComponents(PetscQuadrature, PetscInt);
108 PETSC_EXTERN PetscErrorCode PetscQuadratureEqual(PetscQuadrature, PetscQuadrature, PetscBool *);
109 PETSC_EXTERN PetscErrorCode PetscQuadratureGetData(PetscQuadrature, PetscInt *, PetscInt *, PetscInt *, const PetscReal *[], const PetscReal *[]);
110 PETSC_EXTERN PetscErrorCode PetscQuadratureSetData(PetscQuadrature, PetscInt, PetscInt, PetscInt, const PetscReal[], const PetscReal[]);
111 PETSC_EXTERN PetscErrorCode PetscQuadratureView(PetscQuadrature, PetscViewer);
112 PETSC_EXTERN PetscErrorCode PetscQuadratureDestroy(PetscQuadrature *);
113 
114 PETSC_EXTERN PetscErrorCode PetscDTTensorQuadratureCreate(PetscQuadrature, PetscQuadrature, PetscQuadrature *);
115 PETSC_EXTERN PetscErrorCode PetscQuadratureExpandComposite(PetscQuadrature, PetscInt, const PetscReal[], const PetscReal[], PetscQuadrature *);
116 PETSC_EXTERN PetscErrorCode PetscQuadratureComputePermutations(PetscQuadrature, PetscInt *, IS *[]);
117 
118 PETSC_EXTERN PetscErrorCode PetscQuadraturePushForward(PetscQuadrature, PetscInt, const PetscReal[], const PetscReal[], const PetscReal[], PetscInt, PetscQuadrature *);
119 
120 PETSC_EXTERN PetscErrorCode PetscDTLegendreEval(PetscInt, const PetscReal *, PetscInt, const PetscInt *, PetscReal *, PetscReal *, PetscReal *);
121 PETSC_EXTERN PetscErrorCode PetscDTJacobiNorm(PetscReal, PetscReal, PetscInt, PetscReal *);
122 PETSC_EXTERN PetscErrorCode PetscDTJacobiEval(PetscInt, PetscReal, PetscReal, const PetscReal *, PetscInt, const PetscInt *, PetscReal *, PetscReal *, PetscReal *);
123 PETSC_EXTERN PetscErrorCode PetscDTJacobiEvalJet(PetscReal, PetscReal, PetscInt, const PetscReal[], PetscInt, PetscInt, PetscReal[]);
124 PETSC_EXTERN PetscErrorCode PetscDTPKDEvalJet(PetscInt, PetscInt, const PetscReal[], PetscInt, PetscInt, PetscReal[]);
125 PETSC_EXTERN PetscErrorCode PetscDTPTrimmedSize(PetscInt, PetscInt, PetscInt, PetscInt *);
126 PETSC_EXTERN PetscErrorCode PetscDTPTrimmedEvalJet(PetscInt, PetscInt, const PetscReal[], PetscInt, PetscInt, PetscInt, PetscReal[]);
127 PETSC_EXTERN PetscErrorCode PetscDTGaussQuadrature(PetscInt, PetscReal, PetscReal, PetscReal *, PetscReal *);
128 PETSC_EXTERN PetscErrorCode PetscDTGaussJacobiQuadrature(PetscInt, PetscReal, PetscReal, PetscReal, PetscReal, PetscReal *, PetscReal *);
129 PETSC_EXTERN PetscErrorCode PetscDTGaussLobattoJacobiQuadrature(PetscInt, PetscReal, PetscReal, PetscReal, PetscReal, PetscReal *, PetscReal *);
130 PETSC_EXTERN PetscErrorCode PetscDTGaussLobattoLegendreQuadrature(PetscInt, PetscGaussLobattoLegendreCreateType, PetscReal *, PetscReal *);
131 PETSC_EXTERN PetscErrorCode PetscDTReconstructPoly(PetscInt, PetscInt, const PetscReal *, PetscInt, const PetscReal *, PetscReal *);
132 PETSC_EXTERN PetscErrorCode PetscDTGaussTensorQuadrature(PetscInt, PetscInt, PetscInt, PetscReal, PetscReal, PetscQuadrature *);
133 PETSC_EXTERN PetscErrorCode PetscDTStroudConicalQuadrature(PetscInt, PetscInt, PetscInt, PetscReal, PetscReal, PetscQuadrature *);
134 PETSC_EXTERN PetscErrorCode PetscDTSimplexQuadrature(PetscInt, PetscInt, PetscDTSimplexQuadratureType, PetscQuadrature *);
135 PETSC_EXTERN PetscErrorCode PetscDTCreateDefaultQuadrature(DMPolytopeType, PetscInt, PetscQuadrature *, PetscQuadrature *);
136 PETSC_EXTERN PetscErrorCode PetscDTCreateQuadratureByCell(DMPolytopeType, PetscInt, PetscDTSimplexQuadratureType, PetscQuadrature *, PetscQuadrature *);
137 
138 PETSC_EXTERN PetscErrorCode PetscDTTanhSinhTensorQuadrature(PetscInt, PetscInt, PetscReal, PetscReal, PetscQuadrature *);
139 PETSC_EXTERN PetscErrorCode PetscDTTanhSinhIntegrate(void (*)(const PetscReal[], void *, PetscReal *), PetscReal, PetscReal, PetscInt, void *, PetscReal *);
140 PETSC_EXTERN PetscErrorCode PetscDTTanhSinhIntegrateMPFR(void (*)(const PetscReal[], void *, PetscReal *), PetscReal, PetscReal, PetscInt, void *, PetscReal *);
141 
142 PETSC_EXTERN PetscErrorCode PetscGaussLobattoLegendreIntegrate(PetscInt, PetscReal *, PetscReal *, const PetscReal *, PetscReal *);
143 PETSC_EXTERN PetscErrorCode PetscGaussLobattoLegendreElementLaplacianCreate(PetscInt, PetscReal *, PetscReal *, PetscReal ***);
144 PETSC_EXTERN PetscErrorCode PetscGaussLobattoLegendreElementLaplacianDestroy(PetscInt, PetscReal *, PetscReal *, PetscReal ***);
145 PETSC_EXTERN PetscErrorCode PetscGaussLobattoLegendreElementGradientCreate(PetscInt, PetscReal *, PetscReal *, PetscReal ***, PetscReal ***);
146 PETSC_EXTERN PetscErrorCode PetscGaussLobattoLegendreElementGradientDestroy(PetscInt, PetscReal *, PetscReal *, PetscReal ***, PetscReal ***);
147 PETSC_EXTERN PetscErrorCode PetscGaussLobattoLegendreElementAdvectionCreate(PetscInt, PetscReal *, PetscReal *, PetscReal ***);
148 PETSC_EXTERN PetscErrorCode PetscGaussLobattoLegendreElementAdvectionDestroy(PetscInt, PetscReal *, PetscReal *, PetscReal ***);
149 PETSC_EXTERN PetscErrorCode PetscGaussLobattoLegendreElementMassCreate(PetscInt, PetscReal *, PetscReal *, PetscReal ***);
150 PETSC_EXTERN PetscErrorCode PetscGaussLobattoLegendreElementMassDestroy(PetscInt, PetscReal *, PetscReal *, PetscReal ***);
151 
152 /*MC
153   PETSC_FORM_DEGREE_UNDEFINED - Indicates that a field does not have
154   a well-defined form degree in exterior calculus.
155 
156   Level: advanced
157 
158 .seealso: `PetscDTAltV`, `PetscDualSpaceGetFormDegree()`
159 M*/
160 #define PETSC_FORM_DEGREE_UNDEFINED PETSC_INT_MIN
161 
162 PETSC_EXTERN PetscErrorCode PetscDTAltVApply(PetscInt, PetscInt, const PetscReal *, const PetscReal *, PetscReal *);
163 PETSC_EXTERN PetscErrorCode PetscDTAltVWedge(PetscInt, PetscInt, PetscInt, const PetscReal *, const PetscReal *, PetscReal *);
164 PETSC_EXTERN PetscErrorCode PetscDTAltVWedgeMatrix(PetscInt, PetscInt, PetscInt, const PetscReal *, PetscReal *);
165 PETSC_EXTERN PetscErrorCode PetscDTAltVPullback(PetscInt, PetscInt, const PetscReal *, PetscInt, const PetscReal *, PetscReal *);
166 PETSC_EXTERN PetscErrorCode PetscDTAltVPullbackMatrix(PetscInt, PetscInt, const PetscReal *, PetscInt, PetscReal *);
167 PETSC_EXTERN PetscErrorCode PetscDTAltVInterior(PetscInt, PetscInt, const PetscReal *, const PetscReal *, PetscReal *);
168 PETSC_EXTERN PetscErrorCode PetscDTAltVInteriorMatrix(PetscInt, PetscInt, const PetscReal *, PetscReal *);
169 PETSC_EXTERN PetscErrorCode PetscDTAltVInteriorPattern(PetscInt, PetscInt, PetscInt (*)[3]);
170 PETSC_EXTERN PetscErrorCode PetscDTAltVStar(PetscInt, PetscInt, PetscInt, const PetscReal *, PetscReal *);
171 
172 PETSC_EXTERN PetscErrorCode PetscDTBaryToIndex(PetscInt, PetscInt, const PetscInt[], PetscInt *);
173 PETSC_EXTERN PetscErrorCode PetscDTIndexToBary(PetscInt, PetscInt, PetscInt, PetscInt[]);
174 PETSC_EXTERN PetscErrorCode PetscDTGradedOrderToIndex(PetscInt, const PetscInt[], PetscInt *);
175 PETSC_EXTERN PetscErrorCode PetscDTIndexToGradedOrder(PetscInt, PetscInt, PetscInt[]);
176 
177 #if defined(PETSC_USE_64BIT_INDICES)
178   #define PETSC_FACTORIAL_MAX 20
179   #define PETSC_BINOMIAL_MAX  61
180 #else
181   #define PETSC_FACTORIAL_MAX 12
182   #define PETSC_BINOMIAL_MAX  29
183 #endif
184 
185 /*MC
186    PetscDTFactorial - Approximate n! as a real number
187 
188    Input Parameter:
189 .  n - a non-negative integer
190 
191    Output Parameter:
192 .  factorial - n!
193 
194    Level: beginner
195 
196 .seealso: `PetscDTFactorialInt()`, `PetscDTBinomialInt()`, `PetscDTBinomial()`
197 M*/
PetscDTFactorial(PetscInt n,PetscReal * factorial)198 static inline PetscErrorCode PetscDTFactorial(PetscInt n, PetscReal *factorial)
199 {
200   PetscReal f = 1.0;
201 
202   PetscFunctionBegin;
203   *factorial = -1.0;
204   PetscCheck(n >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Factorial called with negative number %" PetscInt_FMT, n);
205   for (PetscInt i = 1; i < n + 1; ++i) f *= (PetscReal)i;
206   *factorial = f;
207   PetscFunctionReturn(PETSC_SUCCESS);
208 }
209 
210 /*MC
211    PetscDTFactorialInt - Compute n! as an integer
212 
213    Input Parameter:
214 .  n - a non-negative integer
215 
216    Output Parameter:
217 .  factorial - n!
218 
219    Level: beginner
220 
221    Note:
222    This is limited to `n` such that n! can be represented by `PetscInt`, which is 12 if `PetscInt` is a signed 32-bit integer and 20 if `PetscInt` is a signed 64-bit integer.
223 
224 .seealso: `PetscDTFactorial()`, `PetscDTBinomialInt()`, `PetscDTBinomial()`
225 M*/
PetscDTFactorialInt(PetscInt n,PetscInt * factorial)226 static inline PetscErrorCode PetscDTFactorialInt(PetscInt n, PetscInt *factorial)
227 {
228   PetscInt facLookup[13] = {1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880, 3628800, 39916800, 479001600};
229 
230   PetscFunctionBegin;
231   *factorial = -1;
232   PetscCheck(n >= 0 && n <= PETSC_FACTORIAL_MAX, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of elements %" PetscInt_FMT " is not in supported range [0,%d]", n, PETSC_FACTORIAL_MAX);
233   if (n <= 12) {
234     *factorial = facLookup[n];
235   } else {
236     PetscInt f = facLookup[12];
237     PetscInt i;
238 
239     for (i = 13; i < n + 1; ++i) f *= i;
240     *factorial = f;
241   }
242   PetscFunctionReturn(PETSC_SUCCESS);
243 }
244 
245 /*MC
246    PetscDTBinomial - Approximate the binomial coefficient `n` choose `k`
247 
248    Input Parameters:
249 +  n - a non-negative integer
250 -  k - an integer between 0 and `n`, inclusive
251 
252    Output Parameter:
253 .  binomial - approximation of the binomial coefficient `n` choose `k`
254 
255    Level: beginner
256 
257 .seealso: `PetscDTFactorial()`, `PetscDTFactorialInt()`, `PetscDTBinomialInt()`, `PetscDTEnumPerm()`
258 M*/
PetscDTBinomial(PetscInt n,PetscInt k,PetscReal * binomial)259 static inline PetscErrorCode PetscDTBinomial(PetscInt n, PetscInt k, PetscReal *binomial)
260 {
261   PetscFunctionBeginHot;
262   *binomial = -1.0;
263   PetscCheck(n >= 0 && k >= 0 && k <= n, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Binomial arguments (%" PetscInt_FMT " %" PetscInt_FMT ") must be non-negative, k <= n", n, k);
264   if (n <= 3) {
265     PetscInt binomLookup[4][4] = {
266       {1, 0, 0, 0},
267       {1, 1, 0, 0},
268       {1, 2, 1, 0},
269       {1, 3, 3, 1}
270     };
271 
272     *binomial = (PetscReal)binomLookup[n][k];
273   } else {
274     PetscReal binom = 1.0;
275 
276     k = PetscMin(k, n - k);
277     for (PetscInt i = 0; i < k; i++) binom = (binom * (PetscReal)(n - i)) / (PetscReal)(i + 1);
278     *binomial = binom;
279   }
280   PetscFunctionReturn(PETSC_SUCCESS);
281 }
282 
283 /*MC
284    PetscDTBinomialInt - Compute the binomial coefficient `n` choose `k`
285 
286    Input Parameters:
287 +  n - a non-negative integer
288 -  k - an integer between 0 and `n`, inclusive
289 
290    Output Parameter:
291 .  binomial - the binomial coefficient `n` choose `k`
292 
293    Level: beginner
294 
295    Note:
296    This is limited by integers that can be represented by `PetscInt`.
297 
298    Use `PetscDTBinomial()` for real number approximations of larger values
299 
300 .seealso: `PetscDTFactorial()`, `PetscDTFactorialInt()`, `PetscDTBinomial()`, `PetscDTEnumPerm()`
301 M*/
PetscDTBinomialInt(PetscInt n,PetscInt k,PetscInt * binomial)302 static inline PetscErrorCode PetscDTBinomialInt(PetscInt n, PetscInt k, PetscInt *binomial)
303 {
304   PetscInt bin;
305 
306   PetscFunctionBegin;
307   *binomial = -1;
308   PetscCheck(n >= 0 && k >= 0 && k <= n, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Binomial arguments (%" PetscInt_FMT " %" PetscInt_FMT ") must be non-negative, k <= n", n, k);
309   PetscCheck(n <= PETSC_BINOMIAL_MAX, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Binomial elements %" PetscInt_FMT " is larger than max for PetscInt, %d", n, PETSC_BINOMIAL_MAX);
310   if (n <= 3) {
311     PetscInt binomLookup[4][4] = {
312       {1, 0, 0, 0},
313       {1, 1, 0, 0},
314       {1, 2, 1, 0},
315       {1, 3, 3, 1}
316     };
317 
318     bin = binomLookup[n][k];
319   } else {
320     PetscInt binom = 1;
321 
322     k = PetscMin(k, n - k);
323     for (PetscInt i = 0; i < k; i++) binom = (binom * (n - i)) / (i + 1);
324     bin = binom;
325   }
326   *binomial = bin;
327   PetscFunctionReturn(PETSC_SUCCESS);
328 }
329 
330 /* the following inline routines should be not be inline routines and then Fortran binding can be built automatically */
331 #define PeOp
332 
333 /*MC
334    PetscDTEnumPerm - Get a permutation of `n` integers from its encoding into the integers [0, n!) as a sequence of swaps.
335 
336    Input Parameters:
337 +  n - a non-negative integer (see note about limits below)
338 -  k - an integer in [0, n!)
339 
340    Output Parameters:
341 +  perm  - the permuted list of the integers [0, ..., n-1]
342 -  isOdd - if not `NULL`, returns whether the permutation used an even or odd number of swaps.
343 
344    Level: intermediate
345 
346    Notes:
347    A permutation can be described by the operations that convert the lists [0, 1, ..., n-1] into the permutation,
348    by a sequence of swaps, where the ith step swaps whatever number is in ith position with a number that is in
349    some position j >= i.  This swap is encoded as the difference (j - i).  The difference d_i at step i is less than
350    (n - i).  This sequence of n-1 differences [d_0, ..., d_{n-2}] is encoded as the number
351    (n-1)! * d_0 + (n-2)! * d_1 + ... + 1! * d_{n-2}.
352 
353    Limited to `n` such that `n`! can be represented by `PetscInt`, which is 12 if `PetscInt` is a signed 32-bit integer and 20 if `PetscInt` is a signed 64-bit integer.
354 
355 .seealso: `PetscDTFactorial()`, `PetscDTFactorialInt()`, `PetscDTBinomial()`, `PetscDTBinomialInt()`, `PetscDTPermIndex()`
356 M*/
PetscDTEnumPerm(PetscInt n,PetscInt k,PetscInt * perm,PeOp PetscBool * isOdd)357 static inline PetscErrorCode PetscDTEnumPerm(PetscInt n, PetscInt k, PetscInt *perm, PeOp PetscBool *isOdd)
358 {
359   PetscInt  odd = 0;
360   PetscInt  i;
361   PetscInt  work[PETSC_FACTORIAL_MAX];
362   PetscInt *w;
363 
364   PetscFunctionBegin;
365   if (isOdd) *isOdd = PETSC_FALSE;
366   PetscCheck(n >= 0 && n <= PETSC_FACTORIAL_MAX, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of elements %" PetscInt_FMT " is not in supported range [0,%d]", n, PETSC_FACTORIAL_MAX);
367   if (n >= 2) {
368     w = &work[n - 2];
369     for (i = 2; i <= n; i++) {
370       *(w--) = k % i;
371       k /= i;
372     }
373   }
374   for (i = 0; i < n; i++) perm[i] = i;
375   for (i = 0; i < n - 1; i++) {
376     PetscInt s    = work[i];
377     PetscInt swap = perm[i];
378 
379     perm[i]     = perm[i + s];
380     perm[i + s] = swap;
381     odd ^= (!!s);
382   }
383   if (isOdd) *isOdd = odd ? PETSC_TRUE : PETSC_FALSE;
384   PetscFunctionReturn(PETSC_SUCCESS);
385 }
386 
387 /*MC
388    PetscDTPermIndex - Encode a permutation of n into an integer in [0, n!).  This inverts `PetscDTEnumPerm()`.
389 
390    Input Parameters:
391 +  n    - a non-negative integer (see note about limits below)
392 -  perm - the permuted list of the integers [0, ..., n-1]
393 
394    Output Parameters:
395 +  k     - an integer in [0, n!)
396 -  isOdd - if not `NULL`, returns whether the permutation used an even or odd number of swaps.
397 
398    Level: beginner
399 
400    Note:
401    Limited to `n` such that `n`! can be represented by `PetscInt`, which is 12 if `PetscInt` is a signed 32-bit integer and 20 if `PetscInt` is a signed 64-bit integer.
402 
403 .seealso: `PetscDTFactorial()`, `PetscDTFactorialInt()`, `PetscDTBinomial()`, `PetscDTBinomialInt()`, `PetscDTEnumPerm()`
404 M*/
PetscDTPermIndex(PetscInt n,const PetscInt * perm,PetscInt * k,PeOp PetscBool * isOdd)405 static inline PetscErrorCode PetscDTPermIndex(PetscInt n, const PetscInt *perm, PetscInt *k, PeOp PetscBool *isOdd)
406 {
407   PetscInt odd = 0;
408   PetscInt i, idx;
409   PetscInt work[PETSC_FACTORIAL_MAX];
410   PetscInt iwork[PETSC_FACTORIAL_MAX];
411 
412   PetscFunctionBeginHot;
413   *k = -1;
414   if (isOdd) *isOdd = PETSC_FALSE;
415   PetscCheck(n >= 0 && n <= PETSC_FACTORIAL_MAX, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Number of elements %" PetscInt_FMT " is not in supported range [0,%d]", n, PETSC_FACTORIAL_MAX);
416   for (i = 0; i < n; i++) work[i] = i;  /* partial permutation */
417   for (i = 0; i < n; i++) iwork[i] = i; /* partial permutation inverse */
418   for (idx = 0, i = 0; i < n - 1; i++) {
419     PetscInt j    = perm[i];
420     PetscInt icur = work[i];
421     PetscInt jloc = iwork[j];
422     PetscInt diff = jloc - i;
423 
424     idx = idx * (n - i) + diff;
425     /* swap (i, jloc) */
426     work[i]     = j;
427     work[jloc]  = icur;
428     iwork[j]    = i;
429     iwork[icur] = jloc;
430     odd ^= (!!diff);
431   }
432   *k = idx;
433   if (isOdd) *isOdd = odd ? PETSC_TRUE : PETSC_FALSE;
434   PetscFunctionReturn(PETSC_SUCCESS);
435 }
436 
437 /*MC
438    PetscDTEnumSubset - Get an ordered subset of the integers [0, ..., n - 1] from its encoding as an integers in [0, n choose k).
439    The encoding is in lexicographic order.
440 
441    Input Parameters:
442 +  n - a non-negative integer (see note about limits below)
443 .  k - an integer in [0, n]
444 -  j - an index in [0, n choose k)
445 
446    Output Parameter:
447 .  subset - the jth subset of size k of the integers [0, ..., n - 1]
448 
449    Level: beginner
450 
451    Note:
452    Limited by arguments such that `n` choose `k` can be represented by `PetscInt`
453 
454 .seealso: `PetscDTSubsetIndex()`, `PetscDTFactorial()`, `PetscDTFactorialInt()`, `PetscDTBinomial()`, `PetscDTBinomialInt()`, `PetscDTEnumPerm()`, `PetscDTPermIndex()`
455 M*/
PetscDTEnumSubset(PetscInt n,PetscInt k,PetscInt j,PetscInt * subset)456 static inline PetscErrorCode PetscDTEnumSubset(PetscInt n, PetscInt k, PetscInt j, PetscInt *subset)
457 {
458   PetscInt Nk;
459 
460   PetscFunctionBeginHot;
461   PetscCall(PetscDTBinomialInt(n, k, &Nk));
462   for (PetscInt i = 0, l = 0; i < n && l < k; i++) {
463     PetscInt Nminuskminus = (Nk * (k - l)) / (n - i);
464     PetscInt Nminusk      = Nk - Nminuskminus;
465 
466     if (j < Nminuskminus) {
467       subset[l++] = i;
468       Nk          = Nminuskminus;
469     } else {
470       j -= Nminuskminus;
471       Nk = Nminusk;
472     }
473   }
474   PetscFunctionReturn(PETSC_SUCCESS);
475 }
476 
477 /*MC
478    PetscDTSubsetIndex - Convert an ordered subset of k integers from the set [0, ..., n - 1] to its encoding as an integers in [0, n choose k) in lexicographic order.
479    This is the inverse of `PetscDTEnumSubset`.
480 
481    Input Parameters:
482 +  n      - a non-negative integer (see note about limits below)
483 .  k      - an integer in [0, n]
484 -  subset - an ordered subset of the integers [0, ..., n - 1]
485 
486    Output Parameter:
487 .  index - the rank of the subset in lexicographic order
488 
489    Level: beginner
490 
491    Note:
492    Limited by arguments such that `n` choose `k` can be represented by `PetscInt`
493 
494 .seealso: `PetscDTEnumSubset()`, `PetscDTFactorial()`, `PetscDTFactorialInt()`, `PetscDTBinomial()`, `PetscDTBinomialInt()`, `PetscDTEnumPerm()`, `PetscDTPermIndex()`
495 M*/
PetscDTSubsetIndex(PetscInt n,PetscInt k,const PetscInt * subset,PetscInt * index)496 static inline PetscErrorCode PetscDTSubsetIndex(PetscInt n, PetscInt k, const PetscInt *subset, PetscInt *index)
497 {
498   PetscInt j = 0, Nk;
499 
500   PetscFunctionBegin;
501   *index = -1;
502   PetscCall(PetscDTBinomialInt(n, k, &Nk));
503   for (PetscInt i = 0, l = 0; i < n && l < k; i++) {
504     PetscInt Nminuskminus = (Nk * (k - l)) / (n - i);
505     PetscInt Nminusk      = Nk - Nminuskminus;
506 
507     if (subset[l] == i) {
508       l++;
509       Nk = Nminuskminus;
510     } else {
511       j += Nminuskminus;
512       Nk = Nminusk;
513     }
514   }
515   *index = j;
516   PetscFunctionReturn(PETSC_SUCCESS);
517 }
518 
519 /*MC
520    PetscDTEnumSplit - Split the integers [0, ..., n - 1] into two complementary ordered subsets, the first subset of size k and being the jth subset of that size in lexicographic order.
521 
522    Input Parameters:
523 +  n - a non-negative integer (see note about limits below)
524 .  k - an integer in [0, n]
525 -  j - an index in [0, n choose k)
526 
527    Output Parameters:
528 +  perm  - the jth subset of size k of the integers [0, ..., n - 1], followed by its complementary set.
529 -  isOdd - if not `NULL`, return whether perm is an even or odd permutation.
530 
531    Level: beginner
532 
533    Note:
534    Limited by arguments such that `n` choose `k` can be represented by `PetscInt`
535 
536 .seealso: `PetscDTEnumSubset()`, `PetscDTSubsetIndex()`, `PetscDTFactorial()`, `PetscDTFactorialInt()`, `PetscDTBinomial()`, `PetscDTBinomialInt()`, `PetscDTEnumPerm()`,
537           `PetscDTPermIndex()`
538 M*/
PetscDTEnumSplit(PetscInt n,PetscInt k,PetscInt j,PetscInt * perm,PeOp PetscBool * isOdd)539 static inline PetscErrorCode PetscDTEnumSplit(PetscInt n, PetscInt k, PetscInt j, PetscInt *perm, PeOp PetscBool *isOdd)
540 {
541   PetscInt  i, l, m, Nk, odd = 0;
542   PetscInt *subcomp = PetscSafePointerPlusOffset(perm, k);
543 
544   PetscFunctionBegin;
545   if (isOdd) *isOdd = PETSC_FALSE;
546   PetscCall(PetscDTBinomialInt(n, k, &Nk));
547   for (i = 0, l = 0, m = 0; i < n && l < k; i++) {
548     PetscInt Nminuskminus = (Nk * (k - l)) / (n - i);
549     PetscInt Nminusk      = Nk - Nminuskminus;
550 
551     if (j < Nminuskminus) {
552       perm[l++] = i;
553       Nk        = Nminuskminus;
554     } else {
555       subcomp[m++] = i;
556       j -= Nminuskminus;
557       odd ^= ((k - l) & 1);
558       Nk = Nminusk;
559     }
560   }
561   for (; i < n; i++) subcomp[m++] = i;
562   if (isOdd) *isOdd = odd ? PETSC_TRUE : PETSC_FALSE;
563   PetscFunctionReturn(PETSC_SUCCESS);
564 }
565 
566 struct _n_PetscTabulation {
567   PetscInt    K;    /* Indicates a k-jet, namely tabulated derivatives up to order k */
568   PetscInt    Nr;   /* The number of tabulation replicas (often 1) */
569   PetscInt    Np;   /* The number of tabulation points in a replica */
570   PetscInt    Nb;   /* The number of functions tabulated */
571   PetscInt    Nc;   /* The number of function components */
572   PetscInt    cdim; /* The coordinate dimension */
573   PetscReal **T;    /* The tabulation T[K] of functions and their derivatives
574                        T[0] = B[Nr*Np][Nb][Nc]:             The basis function values at quadrature points
575                        T[1] = D[Nr*Np][Nb][Nc][cdim]:       The basis function derivatives at quadrature points
576                        T[2] = H[Nr*Np][Nb][Nc][cdim][cdim]: The basis function second derivatives at quadrature points */
577 };
578 
579 /*S
580    PetscTabulation - PETSc object that manages tabulations for finite element methods.
581 
582    Level: intermediate
583 
584    Note:
585    This is a pointer to a C struct, hence the data in it may be accessed directly.
586 
587    Fortran Note:
588    Use `PetscTabulationGetData()` and `PetscTabulationRestoreData()` to access the arrays in the tabulation.
589 
590    Developer Note:
591    TODO: put the meaning of the struct fields in this manual page
592 
593 .seealso: `PetscTabulationDestroy()`, `PetscFECreateTabulation()`, `PetscFEGetCellTabulation()`
594 S*/
595 typedef struct _n_PetscTabulation *PetscTabulation;
596 
597 /*S
598   PetscProbFn - A prototype of a PDF or CDF used with PETSc probability operations whose names begin with `PetscProb` such as
599   `PetscProbComputeKSStatistic()`.
600 
601   Calling Sequence:
602 + x      - input value
603 . scale  - scale factor, I don't know what this is for
604 - result - the value of the PDF or CDF at the input value
605 
606   Level: beginner
607 
608   Developer Note:
609   Why does this take an array argument for `result` when it seems to be able to output a single value?
610 
611 .seealso: `PetscProbComputeKSStatistic()`, `PetscProbComputeKSStatisticWeighted()`, `PetscPDFMaxwellBoltzmann1D()`
612 S*/
613 typedef PetscErrorCode PetscProbFn(const PetscReal x[], const PetscReal scale[], PetscReal result[]);
614 
615 PETSC_EXTERN_TYPEDEF typedef PetscProbFn *PetscProbFunc PETSC_DEPRECATED_TYPEDEF(3, 24, 0, "PetscProbFn*", );
616 
617 typedef enum {
618   DTPROB_DENSITY_CONSTANT,
619   DTPROB_DENSITY_GAUSSIAN,
620   DTPROB_DENSITY_MAXWELL_BOLTZMANN,
621   DTPROB_NUM_DENSITY
622 } DTProbDensityType;
623 PETSC_EXTERN const char *const DTProbDensityTypes[];
624 
625 PETSC_EXTERN PetscProbFn    PetscPDFMaxwellBoltzmann1D;
626 PETSC_EXTERN PetscProbFn    PetscCDFMaxwellBoltzmann1D;
627 PETSC_EXTERN PetscProbFn    PetscPDFMaxwellBoltzmann2D;
628 PETSC_EXTERN PetscProbFn    PetscCDFMaxwellBoltzmann2D;
629 PETSC_EXTERN PetscProbFn    PetscPDFMaxwellBoltzmann3D;
630 PETSC_EXTERN PetscProbFn    PetscCDFMaxwellBoltzmann3D;
631 PETSC_EXTERN PetscProbFn    PetscPDFGaussian1D;
632 PETSC_EXTERN PetscProbFn    PetscCDFGaussian1D;
633 PETSC_EXTERN PetscProbFn    PetscPDFSampleGaussian1D;
634 PETSC_EXTERN PetscProbFn    PetscPDFGaussian2D;
635 PETSC_EXTERN PetscProbFn    PetscPDFSampleGaussian2D;
636 PETSC_EXTERN PetscProbFn    PetscPDFGaussian3D;
637 PETSC_EXTERN PetscProbFn    PetscPDFSampleGaussian3D;
638 PETSC_EXTERN PetscProbFn    PetscPDFConstant1D;
639 PETSC_EXTERN PetscProbFn    PetscCDFConstant1D;
640 PETSC_EXTERN PetscProbFn    PetscPDFSampleConstant1D;
641 PETSC_EXTERN PetscProbFn    PetscPDFConstant2D;
642 PETSC_EXTERN PetscProbFn    PetscCDFConstant2D;
643 PETSC_EXTERN PetscProbFn    PetscPDFSampleConstant2D;
644 PETSC_EXTERN PetscProbFn    PetscPDFConstant3D;
645 PETSC_EXTERN PetscProbFn    PetscCDFConstant3D;
646 PETSC_EXTERN PetscProbFn    PetscPDFSampleConstant3D;
647 PETSC_EXTERN PetscErrorCode PetscProbCreateFromOptions(PetscInt, const char[], const char[], PetscProbFn **, PetscProbFn **, PetscProbFn **);
648 
649 #include <petscvec.h>
650 
651 PETSC_EXTERN PetscErrorCode PetscProbComputeKSStatistic(Vec, PetscProbFn *, PetscReal *);
652 PETSC_EXTERN PetscErrorCode PetscProbComputeKSStatisticWeighted(Vec, Vec, PetscProbFn *, PetscReal *);
653 PETSC_EXTERN PetscErrorCode PetscProbComputeKSStatisticMagnitude(Vec, PetscProbFn *, PetscReal *);
654