xref: /petsc/src/snes/tutorials/ex28.c (revision 9371c9d470a9602b6d10a8bf50c9b2280a79e45a)
1 static const char help[] = "1D multiphysics prototype with analytic Jacobians to solve individual problems and a coupled problem.\n\n";
2 
3 /* Solve a PDE coupled to an algebraic system in 1D
4  *
5  * PDE (U):
6  *     -(k u_x)_x = 1 on (0,1), subject to u(0) = 0, u(1) = 1
7  * Algebraic (K):
8  *     exp(k-1) + k = 1/(1/(1+u) + 1/(1+u_x^2))
9  *
10  * The discretization places k at staggered points, and a separate DMDA is used for each "physics".
11  *
12  * This example is a prototype for coupling in multi-physics problems, therefore residual evaluation and assembly for
13  * each problem (referred to as U and K) are written separately.  This permits the same "physics" code to be used for
14  * solving each uncoupled problem as well as the coupled system.  In particular, run with -problem_type 0 to solve only
15  * problem U (with K fixed), -problem_type 1 to solve only K (with U fixed), and -problem_type 2 to solve both at once.
16  *
17  * In all cases, a fully-assembled analytic Jacobian is available, so the systems can be solved with a direct solve or
18  * any other standard method.  Additionally, by running with
19  *
20  *   -pack_dm_mat_type nest
21  *
22  * The same code assembles a coupled matrix where each block is stored separately, which allows the use of PCFieldSplit
23  * without copying values to extract submatrices.
24  */
25 
26 #include <petscsnes.h>
27 #include <petscdm.h>
28 #include <petscdmda.h>
29 #include <petscdmcomposite.h>
30 
31 typedef struct _UserCtx *User;
32 struct _UserCtx {
33   PetscInt ptype;
34   DM       pack;
35   Vec      Uloc, Kloc;
36 };
37 
38 static PetscErrorCode FormFunctionLocal_U(User user, DMDALocalInfo *info, const PetscScalar u[], const PetscScalar k[], PetscScalar f[]) {
39   PetscReal hx = 1. / info->mx;
40   PetscInt  i;
41 
42   PetscFunctionBeginUser;
43   for (i = info->xs; i < info->xs + info->xm; i++) {
44     if (i == 0) f[i] = 1. / hx * u[i];
45     else if (i == info->mx - 1) f[i] = 1. / hx * (u[i] - 1.0);
46     else f[i] = hx * ((k[i - 1] * (u[i] - u[i - 1]) - k[i] * (u[i + 1] - u[i])) / (hx * hx) - 1.0);
47   }
48   PetscFunctionReturn(0);
49 }
50 
51 static PetscErrorCode FormFunctionLocal_K(User user, DMDALocalInfo *info, const PetscScalar u[], const PetscScalar k[], PetscScalar f[]) {
52   PetscReal hx = 1. / info->mx;
53   PetscInt  i;
54 
55   PetscFunctionBeginUser;
56   for (i = info->xs; i < info->xs + info->xm; i++) {
57     const PetscScalar ubar = 0.5 * (u[i + 1] + u[i]), gradu = (u[i + 1] - u[i]) / hx, g = 1. + gradu * gradu, w = 1. / (1. + ubar) + 1. / g;
58     f[i] = hx * (PetscExpScalar(k[i] - 1.0) + k[i] - 1. / w);
59   }
60   PetscFunctionReturn(0);
61 }
62 
63 static PetscErrorCode FormFunction_All(SNES snes, Vec X, Vec F, void *ctx) {
64   User          user = (User)ctx;
65   DM            dau, dak;
66   DMDALocalInfo infou, infok;
67   PetscScalar  *u, *k;
68   PetscScalar  *fu, *fk;
69   Vec           Uloc, Kloc, Fu, Fk;
70 
71   PetscFunctionBeginUser;
72   PetscCall(DMCompositeGetEntries(user->pack, &dau, &dak));
73   PetscCall(DMDAGetLocalInfo(dau, &infou));
74   PetscCall(DMDAGetLocalInfo(dak, &infok));
75   PetscCall(DMCompositeGetLocalVectors(user->pack, &Uloc, &Kloc));
76   switch (user->ptype) {
77   case 0:
78     PetscCall(DMGlobalToLocalBegin(dau, X, INSERT_VALUES, Uloc));
79     PetscCall(DMGlobalToLocalEnd(dau, X, INSERT_VALUES, Uloc));
80     PetscCall(DMDAVecGetArray(dau, Uloc, &u));
81     PetscCall(DMDAVecGetArray(dak, user->Kloc, &k));
82     PetscCall(DMDAVecGetArray(dau, F, &fu));
83     PetscCall(FormFunctionLocal_U(user, &infou, u, k, fu));
84     PetscCall(DMDAVecRestoreArray(dau, F, &fu));
85     PetscCall(DMDAVecRestoreArray(dau, Uloc, &u));
86     PetscCall(DMDAVecRestoreArray(dak, user->Kloc, &k));
87     break;
88   case 1:
89     PetscCall(DMGlobalToLocalBegin(dak, X, INSERT_VALUES, Kloc));
90     PetscCall(DMGlobalToLocalEnd(dak, X, INSERT_VALUES, Kloc));
91     PetscCall(DMDAVecGetArray(dau, user->Uloc, &u));
92     PetscCall(DMDAVecGetArray(dak, Kloc, &k));
93     PetscCall(DMDAVecGetArray(dak, F, &fk));
94     PetscCall(FormFunctionLocal_K(user, &infok, u, k, fk));
95     PetscCall(DMDAVecRestoreArray(dak, F, &fk));
96     PetscCall(DMDAVecRestoreArray(dau, user->Uloc, &u));
97     PetscCall(DMDAVecRestoreArray(dak, Kloc, &k));
98     break;
99   case 2:
100     PetscCall(DMCompositeScatter(user->pack, X, Uloc, Kloc));
101     PetscCall(DMDAVecGetArray(dau, Uloc, &u));
102     PetscCall(DMDAVecGetArray(dak, Kloc, &k));
103     PetscCall(DMCompositeGetAccess(user->pack, F, &Fu, &Fk));
104     PetscCall(DMDAVecGetArray(dau, Fu, &fu));
105     PetscCall(DMDAVecGetArray(dak, Fk, &fk));
106     PetscCall(FormFunctionLocal_U(user, &infou, u, k, fu));
107     PetscCall(FormFunctionLocal_K(user, &infok, u, k, fk));
108     PetscCall(DMDAVecRestoreArray(dau, Fu, &fu));
109     PetscCall(DMDAVecRestoreArray(dak, Fk, &fk));
110     PetscCall(DMCompositeRestoreAccess(user->pack, F, &Fu, &Fk));
111     PetscCall(DMDAVecRestoreArray(dau, Uloc, &u));
112     PetscCall(DMDAVecRestoreArray(dak, Kloc, &k));
113     break;
114   }
115   PetscCall(DMCompositeRestoreLocalVectors(user->pack, &Uloc, &Kloc));
116   PetscFunctionReturn(0);
117 }
118 
119 static PetscErrorCode FormJacobianLocal_U(User user, DMDALocalInfo *info, const PetscScalar u[], const PetscScalar k[], Mat Buu) {
120   PetscReal hx = 1. / info->mx;
121   PetscInt  i;
122 
123   PetscFunctionBeginUser;
124   for (i = info->xs; i < info->xs + info->xm; i++) {
125     PetscInt    row = i - info->gxs, cols[] = {row - 1, row, row + 1};
126     PetscScalar val = 1. / hx;
127     if (i == 0) {
128       PetscCall(MatSetValuesLocal(Buu, 1, &row, 1, &row, &val, INSERT_VALUES));
129     } else if (i == info->mx - 1) {
130       PetscCall(MatSetValuesLocal(Buu, 1, &row, 1, &row, &val, INSERT_VALUES));
131     } else {
132       PetscScalar vals[] = {-k[i - 1] / hx, (k[i - 1] + k[i]) / hx, -k[i] / hx};
133       PetscCall(MatSetValuesLocal(Buu, 1, &row, 3, cols, vals, INSERT_VALUES));
134     }
135   }
136   PetscFunctionReturn(0);
137 }
138 
139 static PetscErrorCode FormJacobianLocal_K(User user, DMDALocalInfo *info, const PetscScalar u[], const PetscScalar k[], Mat Bkk) {
140   PetscReal hx = 1. / info->mx;
141   PetscInt  i;
142 
143   PetscFunctionBeginUser;
144   for (i = info->xs; i < info->xs + info->xm; i++) {
145     PetscInt    row    = i - info->gxs;
146     PetscScalar vals[] = {hx * (PetscExpScalar(k[i] - 1.) + (PetscScalar)1.)};
147     PetscCall(MatSetValuesLocal(Bkk, 1, &row, 1, &row, vals, INSERT_VALUES));
148   }
149   PetscFunctionReturn(0);
150 }
151 
152 static PetscErrorCode FormJacobianLocal_UK(User user, DMDALocalInfo *info, DMDALocalInfo *infok, const PetscScalar u[], const PetscScalar k[], Mat Buk) {
153   PetscReal   hx = 1. / info->mx;
154   PetscInt    i;
155   PetscInt    row, cols[2];
156   PetscScalar vals[2];
157 
158   PetscFunctionBeginUser;
159   if (!Buk) PetscFunctionReturn(0); /* Not assembling this block */
160   for (i = info->xs; i < info->xs + info->xm; i++) {
161     if (i == 0 || i == info->mx - 1) continue;
162     row     = i - info->gxs;
163     cols[0] = i - 1 - infok->gxs;
164     vals[0] = (u[i] - u[i - 1]) / hx;
165     cols[1] = i - infok->gxs;
166     vals[1] = (u[i] - u[i + 1]) / hx;
167     PetscCall(MatSetValuesLocal(Buk, 1, &row, 2, cols, vals, INSERT_VALUES));
168   }
169   PetscFunctionReturn(0);
170 }
171 
172 static PetscErrorCode FormJacobianLocal_KU(User user, DMDALocalInfo *info, DMDALocalInfo *infok, const PetscScalar u[], const PetscScalar k[], Mat Bku) {
173   PetscInt  i;
174   PetscReal hx = 1. / (info->mx - 1);
175 
176   PetscFunctionBeginUser;
177   if (!Bku) PetscFunctionReturn(0); /* Not assembling this block */
178   for (i = infok->xs; i < infok->xs + infok->xm; i++) {
179     PetscInt          row = i - infok->gxs, cols[2];
180     PetscScalar       vals[2];
181     const PetscScalar ubar = 0.5 * (u[i] + u[i + 1]), ubar_L = 0.5, ubar_R = 0.5, gradu = (u[i + 1] - u[i]) / hx, gradu_L = -1. / hx, gradu_R = 1. / hx, g = 1. + PetscSqr(gradu), g_gradu = 2. * gradu, w = 1. / (1. + ubar) + 1. / g, w_ubar = -1. / PetscSqr(1. + ubar), w_gradu = -g_gradu / PetscSqr(g), iw = 1. / w, iw_ubar = -w_ubar * PetscSqr(iw), iw_gradu = -w_gradu * PetscSqr(iw);
182     cols[0] = i - info->gxs;
183     vals[0] = -hx * (iw_ubar * ubar_L + iw_gradu * gradu_L);
184     cols[1] = i + 1 - info->gxs;
185     vals[1] = -hx * (iw_ubar * ubar_R + iw_gradu * gradu_R);
186     PetscCall(MatSetValuesLocal(Bku, 1, &row, 2, cols, vals, INSERT_VALUES));
187   }
188   PetscFunctionReturn(0);
189 }
190 
191 static PetscErrorCode FormJacobian_All(SNES snes, Vec X, Mat J, Mat B, void *ctx) {
192   User          user = (User)ctx;
193   DM            dau, dak;
194   DMDALocalInfo infou, infok;
195   PetscScalar  *u, *k;
196   Vec           Uloc, Kloc;
197 
198   PetscFunctionBeginUser;
199   PetscCall(DMCompositeGetEntries(user->pack, &dau, &dak));
200   PetscCall(DMDAGetLocalInfo(dau, &infou));
201   PetscCall(DMDAGetLocalInfo(dak, &infok));
202   PetscCall(DMCompositeGetLocalVectors(user->pack, &Uloc, &Kloc));
203   switch (user->ptype) {
204   case 0:
205     PetscCall(DMGlobalToLocalBegin(dau, X, INSERT_VALUES, Uloc));
206     PetscCall(DMGlobalToLocalEnd(dau, X, INSERT_VALUES, Uloc));
207     PetscCall(DMDAVecGetArray(dau, Uloc, &u));
208     PetscCall(DMDAVecGetArray(dak, user->Kloc, &k));
209     PetscCall(FormJacobianLocal_U(user, &infou, u, k, B));
210     PetscCall(DMDAVecRestoreArray(dau, Uloc, &u));
211     PetscCall(DMDAVecRestoreArray(dak, user->Kloc, &k));
212     break;
213   case 1:
214     PetscCall(DMGlobalToLocalBegin(dak, X, INSERT_VALUES, Kloc));
215     PetscCall(DMGlobalToLocalEnd(dak, X, INSERT_VALUES, Kloc));
216     PetscCall(DMDAVecGetArray(dau, user->Uloc, &u));
217     PetscCall(DMDAVecGetArray(dak, Kloc, &k));
218     PetscCall(FormJacobianLocal_K(user, &infok, u, k, B));
219     PetscCall(DMDAVecRestoreArray(dau, user->Uloc, &u));
220     PetscCall(DMDAVecRestoreArray(dak, Kloc, &k));
221     break;
222   case 2: {
223     Mat       Buu, Buk, Bku, Bkk;
224     PetscBool nest;
225     IS       *is;
226     PetscCall(DMCompositeScatter(user->pack, X, Uloc, Kloc));
227     PetscCall(DMDAVecGetArray(dau, Uloc, &u));
228     PetscCall(DMDAVecGetArray(dak, Kloc, &k));
229     PetscCall(DMCompositeGetLocalISs(user->pack, &is));
230     PetscCall(MatGetLocalSubMatrix(B, is[0], is[0], &Buu));
231     PetscCall(MatGetLocalSubMatrix(B, is[0], is[1], &Buk));
232     PetscCall(MatGetLocalSubMatrix(B, is[1], is[0], &Bku));
233     PetscCall(MatGetLocalSubMatrix(B, is[1], is[1], &Bkk));
234     PetscCall(FormJacobianLocal_U(user, &infou, u, k, Buu));
235     PetscCall(PetscObjectTypeCompare((PetscObject)B, MATNEST, &nest));
236     if (!nest) {
237       /*
238          DMCreateMatrix_Composite()  for a nested matrix does not generate off-block matrices that one can call MatSetValuesLocal() on, it just creates dummy
239          matrices with no entries; there cannot insert values into them. Commit b6480e041dd2293a65f96222772d68cdb4ed6306
240          changed Mat_Nest() from returning NULL pointers for these submatrices to dummy matrices because PCFIELDSPLIT could not
241          handle the returned null matrices.
242       */
243       PetscCall(FormJacobianLocal_UK(user, &infou, &infok, u, k, Buk));
244       PetscCall(FormJacobianLocal_KU(user, &infou, &infok, u, k, Bku));
245     }
246     PetscCall(FormJacobianLocal_K(user, &infok, u, k, Bkk));
247     PetscCall(MatRestoreLocalSubMatrix(B, is[0], is[0], &Buu));
248     PetscCall(MatRestoreLocalSubMatrix(B, is[0], is[1], &Buk));
249     PetscCall(MatRestoreLocalSubMatrix(B, is[1], is[0], &Bku));
250     PetscCall(MatRestoreLocalSubMatrix(B, is[1], is[1], &Bkk));
251     PetscCall(DMDAVecRestoreArray(dau, Uloc, &u));
252     PetscCall(DMDAVecRestoreArray(dak, Kloc, &k));
253 
254     PetscCall(ISDestroy(&is[0]));
255     PetscCall(ISDestroy(&is[1]));
256     PetscCall(PetscFree(is));
257   } break;
258   }
259   PetscCall(DMCompositeRestoreLocalVectors(user->pack, &Uloc, &Kloc));
260   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
261   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
262   if (J != B) {
263     PetscCall(MatAssemblyBegin(J, MAT_FINAL_ASSEMBLY));
264     PetscCall(MatAssemblyEnd(J, MAT_FINAL_ASSEMBLY));
265   }
266   PetscFunctionReturn(0);
267 }
268 
269 static PetscErrorCode FormInitial_Coupled(User user, Vec X) {
270   DM            dau, dak;
271   DMDALocalInfo infou, infok;
272   Vec           Xu, Xk;
273   PetscScalar  *u, *k, hx;
274   PetscInt      i;
275 
276   PetscFunctionBeginUser;
277   PetscCall(DMCompositeGetEntries(user->pack, &dau, &dak));
278   PetscCall(DMCompositeGetAccess(user->pack, X, &Xu, &Xk));
279   PetscCall(DMDAVecGetArray(dau, Xu, &u));
280   PetscCall(DMDAVecGetArray(dak, Xk, &k));
281   PetscCall(DMDAGetLocalInfo(dau, &infou));
282   PetscCall(DMDAGetLocalInfo(dak, &infok));
283   hx = 1. / (infok.mx);
284   for (i = infou.xs; i < infou.xs + infou.xm; i++) u[i] = (PetscScalar)i * hx * (1. - (PetscScalar)i * hx);
285   for (i = infok.xs; i < infok.xs + infok.xm; i++) k[i] = 1.0 + 0.5 * PetscSinScalar(2 * PETSC_PI * i * hx);
286   PetscCall(DMDAVecRestoreArray(dau, Xu, &u));
287   PetscCall(DMDAVecRestoreArray(dak, Xk, &k));
288   PetscCall(DMCompositeRestoreAccess(user->pack, X, &Xu, &Xk));
289   PetscCall(DMCompositeScatter(user->pack, X, user->Uloc, user->Kloc));
290   PetscFunctionReturn(0);
291 }
292 
293 int main(int argc, char *argv[]) {
294   DM              dau, dak, pack;
295   const PetscInt *lxu;
296   PetscInt       *lxk, m, sizes;
297   User            user;
298   SNES            snes;
299   Vec             X, F, Xu, Xk, Fu, Fk;
300   Mat             B;
301   IS             *isg;
302   PetscBool       pass_dm;
303 
304   PetscFunctionBeginUser;
305   PetscCall(PetscInitialize(&argc, &argv, 0, help));
306   PetscCall(DMDACreate1d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, 10, 1, 1, NULL, &dau));
307   PetscCall(DMSetOptionsPrefix(dau, "u_"));
308   PetscCall(DMSetFromOptions(dau));
309   PetscCall(DMSetUp(dau));
310   PetscCall(DMDAGetOwnershipRanges(dau, &lxu, 0, 0));
311   PetscCall(DMDAGetInfo(dau, 0, &m, 0, 0, &sizes, 0, 0, 0, 0, 0, 0, 0, 0));
312   PetscCall(PetscMalloc1(sizes, &lxk));
313   PetscCall(PetscArraycpy(lxk, lxu, sizes));
314   lxk[0]--;
315   PetscCall(DMDACreate1d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, m - 1, 1, 1, lxk, &dak));
316   PetscCall(DMSetOptionsPrefix(dak, "k_"));
317   PetscCall(DMSetFromOptions(dak));
318   PetscCall(DMSetUp(dak));
319   PetscCall(PetscFree(lxk));
320 
321   PetscCall(DMCompositeCreate(PETSC_COMM_WORLD, &pack));
322   PetscCall(DMSetOptionsPrefix(pack, "pack_"));
323   PetscCall(DMCompositeAddDM(pack, dau));
324   PetscCall(DMCompositeAddDM(pack, dak));
325   PetscCall(DMDASetFieldName(dau, 0, "u"));
326   PetscCall(DMDASetFieldName(dak, 0, "k"));
327   PetscCall(DMSetFromOptions(pack));
328 
329   PetscCall(DMCreateGlobalVector(pack, &X));
330   PetscCall(VecDuplicate(X, &F));
331 
332   PetscCall(PetscNew(&user));
333 
334   user->pack = pack;
335 
336   PetscCall(DMCompositeGetGlobalISs(pack, &isg));
337   PetscCall(DMCompositeGetLocalVectors(pack, &user->Uloc, &user->Kloc));
338   PetscCall(DMCompositeScatter(pack, X, user->Uloc, user->Kloc));
339 
340   PetscOptionsBegin(PETSC_COMM_WORLD, NULL, "Coupled problem options", "SNES");
341   {
342     user->ptype = 0;
343     pass_dm     = PETSC_TRUE;
344 
345     PetscCall(PetscOptionsInt("-problem_type", "0: solve for u only, 1: solve for k only, 2: solve for both", 0, user->ptype, &user->ptype, NULL));
346     PetscCall(PetscOptionsBool("-pass_dm", "Pass the packed DM to SNES to use when determining splits and forward into splits", 0, pass_dm, &pass_dm, NULL));
347   }
348   PetscOptionsEnd();
349 
350   PetscCall(FormInitial_Coupled(user, X));
351 
352   PetscCall(SNESCreate(PETSC_COMM_WORLD, &snes));
353   switch (user->ptype) {
354   case 0:
355     PetscCall(DMCompositeGetAccess(pack, X, &Xu, 0));
356     PetscCall(DMCompositeGetAccess(pack, F, &Fu, 0));
357     PetscCall(DMCreateMatrix(dau, &B));
358     PetscCall(SNESSetFunction(snes, Fu, FormFunction_All, user));
359     PetscCall(SNESSetJacobian(snes, B, B, FormJacobian_All, user));
360     PetscCall(SNESSetFromOptions(snes));
361     PetscCall(SNESSetDM(snes, dau));
362     PetscCall(SNESSolve(snes, NULL, Xu));
363     PetscCall(DMCompositeRestoreAccess(pack, X, &Xu, 0));
364     PetscCall(DMCompositeRestoreAccess(pack, F, &Fu, 0));
365     break;
366   case 1:
367     PetscCall(DMCompositeGetAccess(pack, X, 0, &Xk));
368     PetscCall(DMCompositeGetAccess(pack, F, 0, &Fk));
369     PetscCall(DMCreateMatrix(dak, &B));
370     PetscCall(SNESSetFunction(snes, Fk, FormFunction_All, user));
371     PetscCall(SNESSetJacobian(snes, B, B, FormJacobian_All, user));
372     PetscCall(SNESSetFromOptions(snes));
373     PetscCall(SNESSetDM(snes, dak));
374     PetscCall(SNESSolve(snes, NULL, Xk));
375     PetscCall(DMCompositeRestoreAccess(pack, X, 0, &Xk));
376     PetscCall(DMCompositeRestoreAccess(pack, F, 0, &Fk));
377     break;
378   case 2:
379     PetscCall(DMCreateMatrix(pack, &B));
380     /* This example does not correctly allocate off-diagonal blocks. These options allows new nonzeros (slow). */
381     PetscCall(MatSetOption(B, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_FALSE));
382     PetscCall(MatSetOption(B, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_FALSE));
383     PetscCall(SNESSetFunction(snes, F, FormFunction_All, user));
384     PetscCall(SNESSetJacobian(snes, B, B, FormJacobian_All, user));
385     PetscCall(SNESSetFromOptions(snes));
386     if (!pass_dm) { /* Manually provide index sets and names for the splits */
387       KSP ksp;
388       PC  pc;
389       PetscCall(SNESGetKSP(snes, &ksp));
390       PetscCall(KSPGetPC(ksp, &pc));
391       PetscCall(PCFieldSplitSetIS(pc, "u", isg[0]));
392       PetscCall(PCFieldSplitSetIS(pc, "k", isg[1]));
393     } else {
394       /* The same names come from the options prefix for dau and dak. This option can support geometric multigrid inside
395        * of splits, but it requires using a DM (perhaps your own implementation). */
396       PetscCall(SNESSetDM(snes, pack));
397     }
398     PetscCall(SNESSolve(snes, NULL, X));
399     break;
400   }
401   PetscCall(VecViewFromOptions(X, NULL, "-view_sol"));
402 
403   if (0) {
404     PetscInt  col      = 0;
405     PetscBool mult_dup = PETSC_FALSE, view_dup = PETSC_FALSE;
406     Mat       D;
407     Vec       Y;
408 
409     PetscCall(PetscOptionsGetInt(NULL, 0, "-col", &col, 0));
410     PetscCall(PetscOptionsGetBool(NULL, 0, "-mult_dup", &mult_dup, 0));
411     PetscCall(PetscOptionsGetBool(NULL, 0, "-view_dup", &view_dup, 0));
412 
413     PetscCall(VecDuplicate(X, &Y));
414     /* PetscCall(MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY)); */
415     /* PetscCall(MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY)); */
416     PetscCall(MatConvert(B, MATAIJ, MAT_INITIAL_MATRIX, &D));
417     PetscCall(VecZeroEntries(X));
418     PetscCall(VecSetValue(X, col, 1.0, INSERT_VALUES));
419     PetscCall(VecAssemblyBegin(X));
420     PetscCall(VecAssemblyEnd(X));
421     PetscCall(MatMult(mult_dup ? D : B, X, Y));
422     PetscCall(MatView(view_dup ? D : B, PETSC_VIEWER_STDOUT_WORLD));
423     /* PetscCall(VecView(X,PETSC_VIEWER_STDOUT_WORLD)); */
424     PetscCall(VecView(Y, PETSC_VIEWER_STDOUT_WORLD));
425     PetscCall(MatDestroy(&D));
426     PetscCall(VecDestroy(&Y));
427   }
428 
429   PetscCall(DMCompositeRestoreLocalVectors(pack, &user->Uloc, &user->Kloc));
430   PetscCall(PetscFree(user));
431 
432   PetscCall(ISDestroy(&isg[0]));
433   PetscCall(ISDestroy(&isg[1]));
434   PetscCall(PetscFree(isg));
435   PetscCall(VecDestroy(&X));
436   PetscCall(VecDestroy(&F));
437   PetscCall(MatDestroy(&B));
438   PetscCall(DMDestroy(&dau));
439   PetscCall(DMDestroy(&dak));
440   PetscCall(DMDestroy(&pack));
441   PetscCall(SNESDestroy(&snes));
442   PetscCall(PetscFinalize());
443   return 0;
444 }
445 
446 /*TEST
447 
448    test:
449       suffix: 0
450       nsize: 3
451       args: -u_da_grid_x 20 -snes_converged_reason -snes_monitor_short -problem_type 0
452 
453    test:
454       suffix: 1
455       nsize: 3
456       args: -u_da_grid_x 20 -snes_converged_reason -snes_monitor_short -problem_type 1
457 
458    test:
459       suffix: 2
460       nsize: 3
461       args: -u_da_grid_x 20 -snes_converged_reason -snes_monitor_short -problem_type 2
462 
463    test:
464       suffix: 3
465       nsize: 3
466       args: -u_da_grid_x 20 -snes_converged_reason -snes_monitor_short -ksp_monitor_short -problem_type 2 -snes_mf_operator -pack_dm_mat_type {{aij nest}} -pc_type fieldsplit -pc_fieldsplit_dm_splits -pc_fieldsplit_type additive -fieldsplit_u_ksp_type gmres -fieldsplit_k_pc_type jacobi
467 
468    test:
469       suffix: 4
470       nsize: 6
471       args: -u_da_grid_x 257 -snes_converged_reason -snes_monitor_short -ksp_monitor_short -problem_type 2 -snes_mf_operator -pack_dm_mat_type aij -pc_type fieldsplit -pc_fieldsplit_type multiplicative -fieldsplit_u_ksp_type gmres -fieldsplit_u_ksp_pc_side right -fieldsplit_u_pc_type mg -fieldsplit_u_pc_mg_levels 4 -fieldsplit_u_mg_levels_ksp_type richardson -fieldsplit_u_mg_levels_ksp_max_it 1 -fieldsplit_u_mg_levels_pc_type sor -fieldsplit_u_pc_mg_galerkin pmat -fieldsplit_u_ksp_converged_reason -fieldsplit_k_pc_type jacobi
472       requires: !single
473 
474    test:
475       suffix: glvis_composite_da_1d
476       args: -u_da_grid_x 20 -problem_type 0 -snes_monitor_solution glvis:
477 
478    test:
479       suffix: cuda
480       nsize: 1
481       requires: cuda
482       args: -u_da_grid_x 20 -snes_converged_reason -snes_monitor_short -problem_type 2 -pack_dm_mat_type aijcusparse -pack_dm_vec_type cuda
483 
484    test:
485       suffix: viennacl
486       nsize: 1
487       requires: viennacl
488       args: -u_da_grid_x 20 -snes_converged_reason -snes_monitor_short -problem_type 2 -pack_dm_mat_type aijviennacl -pack_dm_vec_type viennacl
489 
490 TEST*/
491