xref: /petsc/src/tao/tutorials/ex1.c (revision 7a7aea1f13832695eadc2fd5afef8ec0a48c5f75)
1 static char help[] = "One-Shot Multigrid for Parameter Estimation Problem for the Poisson Equation.\n\
2 Using the Interior Point Method.\n\n\n";
3 
4 /*F
5   We are solving the parameter estimation problem for the Laplacian. We will ask to minimize a Lagrangian
6 function over $a$ and $u$, given by
7 \begin{align}
8   L(u, a, \lambda) = \frac{1}{2} || Qu - d ||^2 + \frac{1}{2} || L (a - a_r) ||^2 + \lambda F(u; a)
9 \end{align}
10 where $Q$ is a sampling operator, $L$ is a regularization operator, $F$ defines the PDE.
11 
12 Currently, we have perfect information, meaning $Q = I$, and then we need no regularization, $L = I$. We
13 also give the exact control for the reference $a_r$.
14 
15 The PDE will be the Laplace equation with homogeneous boundary conditions
16 \begin{align}
17   -nabla \cdot a \nabla u = f
18 \end{align}
19 
20 F*/
21 
22 #include <petsc.h>
23 #include <petscfe.h>
24 
25 typedef enum {RUN_FULL, RUN_TEST} RunType;
26 
27 typedef struct {
28   RunType runType;  /* Whether to run tests, or solve the full problem */
29   PetscErrorCode (**exactFuncs)(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *u, void *ctx);
30 } AppCtx;
31 
32 static PetscErrorCode ProcessOptions(MPI_Comm comm, AppCtx *options)
33 {
34   const char    *runTypes[2] = {"full", "test"};
35   PetscInt       run;
36   PetscErrorCode ierr;
37 
38   PetscFunctionBeginUser;
39   options->runType = RUN_FULL;
40 
41   ierr = PetscOptionsBegin(comm, "", "Inverse Problem Options", "DMPLEX");CHKERRQ(ierr);
42   run  = options->runType;
43   ierr = PetscOptionsEList("-run_type", "The run type", "ex1.c", runTypes, 2, runTypes[options->runType], &run, NULL);CHKERRQ(ierr);
44   options->runType = (RunType) run;
45   ierr = PetscOptionsEnd();CHKERRQ(ierr);
46   PetscFunctionReturn(0);
47 }
48 
49 static PetscErrorCode CreateMesh(MPI_Comm comm, AppCtx *user, DM *dm)
50 {
51   DM             distributedMesh = NULL;
52   PetscErrorCode ierr;
53 
54   PetscFunctionBeginUser;
55   ierr = DMPlexCreateBoxMesh(comm, 2, PETSC_TRUE, NULL, NULL, NULL, NULL, PETSC_TRUE, dm);CHKERRQ(ierr);
56   ierr = PetscObjectSetName((PetscObject) *dm, "Mesh");CHKERRQ(ierr);
57   ierr = DMPlexDistribute(*dm, 0, NULL, &distributedMesh);CHKERRQ(ierr);
58   if (distributedMesh) {
59     ierr = DMDestroy(dm);CHKERRQ(ierr);
60     *dm  = distributedMesh;
61   }
62   ierr = DMSetFromOptions(*dm);CHKERRQ(ierr);
63   ierr = DMViewFromOptions(*dm, NULL, "-dm_view");CHKERRQ(ierr);
64   PetscFunctionReturn(0);
65 }
66 
67 /* u - (x^2 + y^2) */
68 void f0_u(PetscInt dim, PetscInt Nf, PetscInt NfAux,
69           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
70           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
71           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
72 {
73   f0[0] = u[0] - (x[0]*x[0] + x[1]*x[1]);
74 }
75 /* a \nabla\lambda */
76 void f1_u(PetscInt dim, PetscInt Nf, PetscInt NfAux,
77           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
78           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
79           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f1[])
80 {
81   PetscInt d;
82   for (d = 0; d < dim; ++d) f1[d] = u[1]*u_x[dim*2+d];
83 }
84 /* I */
85 void g0_uu(PetscInt dim, PetscInt Nf, PetscInt NfAux,
86            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
87            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
88            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g0[])
89 {
90   g0[0] = 1.0;
91 }
92 /* \nabla */
93 void g2_ua(PetscInt dim, PetscInt Nf, PetscInt NfAux,
94            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
95            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
96            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g2[])
97 {
98   PetscInt d;
99   for (d = 0; d < dim; ++d) g2[d] = u_x[dim*2+d];
100 }
101 /* a */
102 void g3_ul(PetscInt dim, PetscInt Nf, PetscInt NfAux,
103            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
104            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
105            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g3[])
106 {
107   PetscInt d;
108   for (d = 0; d < dim; ++d) g3[d*dim+d] = u[1];
109 }
110 /* a - (x + y) */
111 void f0_a(PetscInt dim, PetscInt Nf, PetscInt NfAux,
112           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
113           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
114           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
115 {
116   f0[0] = u[1] - (x[0] + x[1]);
117 }
118 /* \lambda \nabla u */
119 void f1_a(PetscInt dim, PetscInt Nf, PetscInt NfAux,
120           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
121           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
122           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f1[])
123 {
124   PetscInt d;
125   for (d = 0; d < dim; ++d) f1[d] = u[2]*u_x[d];
126 }
127 /* I */
128 void g0_aa(PetscInt dim, PetscInt Nf, PetscInt NfAux,
129            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
130            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
131            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g0[])
132 {
133   g0[0] = 1.0;
134 }
135 /* 6 (x + y) */
136 void f0_l(PetscInt dim, PetscInt Nf, PetscInt NfAux,
137           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
138           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
139           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
140 {
141   f0[0] = 6.0*(x[0] + x[1]);
142 }
143 /* a \nabla u */
144 void f1_l(PetscInt dim, PetscInt Nf, PetscInt NfAux,
145           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
146           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
147           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f1[])
148 {
149   PetscInt d;
150   for (d = 0; d < dim; ++d) f1[d] = u[1]*u_x[d];
151 }
152 /* \nabla u */
153 void g2_la(PetscInt dim, PetscInt Nf, PetscInt NfAux,
154            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
155            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
156            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g2[])
157 {
158   PetscInt d;
159   for (d = 0; d < dim; ++d) g2[d] = u_x[d];
160 }
161 /* a */
162 void g3_lu(PetscInt dim, PetscInt Nf, PetscInt NfAux,
163            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
164            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
165            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g3[])
166 {
167   PetscInt d;
168   for (d = 0; d < dim; ++d) g3[d*dim+d] = u[1];
169 }
170 
171 /*
172   In 2D for Dirichlet conditions with a variable coefficient, we use exact solution:
173 
174     u  = x^2 + y^2
175     f  = 6 (x + y)
176     kappa(a) = a = (x + y)
177 
178   so that
179 
180     -\div \kappa(a) \grad u + f = -6 (x + y) + 6 (x + y) = 0
181 */
182 PetscErrorCode quadratic_u_2d(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *u, void *ctx)
183 {
184   *u = x[0]*x[0] + x[1]*x[1];
185   return 0;
186 }
187 PetscErrorCode linear_a_2d(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *a, void *ctx)
188 {
189   *a = x[0] + x[1];
190   return 0;
191 }
192 PetscErrorCode zero(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *l, void *ctx)
193 {
194   *l = 0.0;
195   return 0;
196 }
197 
198 PetscErrorCode SetupProblem(DM dm, AppCtx *user)
199 {
200   PetscDS        prob;
201   const PetscInt id = 1;
202   PetscErrorCode ierr;
203 
204   PetscFunctionBeginUser;
205   ierr = DMGetDS(dm, &prob);CHKERRQ(ierr);
206   ierr = PetscDSSetResidual(prob, 0, f0_u, f1_u);CHKERRQ(ierr);
207   ierr = PetscDSSetResidual(prob, 1, f0_a, f1_a);CHKERRQ(ierr);
208   ierr = PetscDSSetResidual(prob, 2, f0_l, f1_l);CHKERRQ(ierr);
209   ierr = PetscDSSetJacobian(prob, 0, 0, g0_uu, NULL, NULL, NULL);CHKERRQ(ierr);
210   ierr = PetscDSSetJacobian(prob, 0, 1, NULL, NULL, g2_ua, NULL);CHKERRQ(ierr);
211   ierr = PetscDSSetJacobian(prob, 0, 2, NULL, NULL, NULL, g3_ul);CHKERRQ(ierr);
212   ierr = PetscDSSetJacobian(prob, 1, 1, g0_aa, NULL, NULL, NULL);CHKERRQ(ierr);
213   ierr = PetscDSSetJacobian(prob, 2, 1, NULL, NULL, g2_la, NULL);CHKERRQ(ierr);
214   ierr = PetscDSSetJacobian(prob, 2, 0, NULL, NULL, NULL, g3_lu);CHKERRQ(ierr);
215 
216   user->exactFuncs[0] = quadratic_u_2d;
217   user->exactFuncs[1] = linear_a_2d;
218   user->exactFuncs[2] = zero;
219   ierr = PetscDSAddBoundary(prob, DM_BC_ESSENTIAL, "wall", "marker", 0, 0, NULL, (void (*)(void)) user->exactFuncs[0], 1, &id, user);CHKERRQ(ierr);
220   ierr = PetscDSAddBoundary(prob, DM_BC_ESSENTIAL, "wall", "marker", 1, 0, NULL, (void (*)(void)) user->exactFuncs[1], 1, &id, user);CHKERRQ(ierr);
221   ierr = PetscDSAddBoundary(prob, DM_BC_ESSENTIAL, "wall", "marker", 2, 0, NULL, (void (*)(void)) user->exactFuncs[2], 1, &id, user);CHKERRQ(ierr);
222   PetscFunctionReturn(0);
223 }
224 
225 PetscErrorCode SetupDiscretization(DM dm, AppCtx *user)
226 {
227   DM              cdm = dm;
228   const PetscInt  dim = 2;
229   PetscFE         fe[3];
230   PetscInt        f;
231   MPI_Comm        comm;
232   PetscErrorCode  ierr;
233 
234   PetscFunctionBeginUser;
235   /* Create finite element */
236   ierr = PetscObjectGetComm((PetscObject) dm, &comm);CHKERRQ(ierr);
237   ierr = PetscFECreateDefault(comm, dim, 1, PETSC_TRUE, "potential_", -1, &fe[0]);CHKERRQ(ierr);
238   ierr = PetscObjectSetName((PetscObject) fe[0], "potential");CHKERRQ(ierr);
239   ierr = PetscFECreateDefault(comm, dim, 1, PETSC_TRUE, "conductivity_", -1, &fe[1]);CHKERRQ(ierr);
240   ierr = PetscObjectSetName((PetscObject) fe[1], "conductivity");CHKERRQ(ierr);
241   ierr = PetscFECopyQuadrature(fe[0], fe[1]);CHKERRQ(ierr);
242   ierr = PetscFECreateDefault(comm, dim, 1, PETSC_TRUE, "multiplier_", -1, &fe[2]);CHKERRQ(ierr);
243   ierr = PetscObjectSetName((PetscObject) fe[2], "multiplier");CHKERRQ(ierr);
244   ierr = PetscFECopyQuadrature(fe[0], fe[2]);CHKERRQ(ierr);
245   /* Set discretization and boundary conditions for each mesh */
246   for (f = 0; f < 3; ++f) {ierr = DMSetField(dm, f, NULL, (PetscObject) fe[f]);CHKERRQ(ierr);}
247   ierr = DMCreateDS(dm);CHKERRQ(ierr);
248   ierr = SetupProblem(dm, user);CHKERRQ(ierr);
249   while (cdm) {
250     ierr = DMCopyDisc(dm, cdm);CHKERRQ(ierr);
251     ierr = DMGetCoarseDM(cdm, &cdm);CHKERRQ(ierr);
252   }
253   for (f = 0; f < 3; ++f) {ierr = PetscFEDestroy(&fe[f]);CHKERRQ(ierr);}
254   PetscFunctionReturn(0);
255 }
256 
257 int main(int argc, char **argv)
258 {
259   DM             dm;
260   SNES           snes;
261   Vec            u, r;
262   AppCtx         user;
263   PetscErrorCode ierr;
264 
265   ierr = PetscInitialize(&argc, &argv, NULL,help);if (ierr) return ierr;
266   ierr = ProcessOptions(PETSC_COMM_WORLD, &user);CHKERRQ(ierr);
267   ierr = SNESCreate(PETSC_COMM_WORLD, &snes);CHKERRQ(ierr);
268   ierr = CreateMesh(PETSC_COMM_WORLD, &user, &dm);CHKERRQ(ierr);
269   ierr = SNESSetDM(snes, dm);CHKERRQ(ierr);
270 
271   ierr = PetscMalloc(3 * sizeof(void (*)()), &user.exactFuncs);CHKERRQ(ierr);
272   ierr = SetupDiscretization(dm, &user);CHKERRQ(ierr);
273 
274   ierr = DMCreateGlobalVector(dm, &u);CHKERRQ(ierr);
275   ierr = PetscObjectSetName((PetscObject) u, "solution");CHKERRQ(ierr);
276   ierr = VecDuplicate(u, &r);CHKERRQ(ierr);
277   ierr = DMPlexSetSNESLocalFEM(dm,&user,&user,&user);CHKERRQ(ierr);
278   ierr = SNESSetFromOptions(snes);CHKERRQ(ierr);
279 
280   ierr = DMProjectFunction(dm, 0.0, user.exactFuncs, NULL, INSERT_ALL_VALUES, u);CHKERRQ(ierr);
281   ierr = DMSNESCheckFromOptions(snes, u, user.exactFuncs, NULL);CHKERRQ(ierr);
282   if (user.runType == RUN_FULL) {
283     PetscErrorCode (*initialGuess[3])(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar u[], void *ctx);
284     PetscReal        error;
285 
286     initialGuess[0] = zero;
287     initialGuess[1] = zero;
288     initialGuess[2] = zero;
289     ierr = DMProjectFunction(dm, 0.0, initialGuess, NULL, INSERT_VALUES, u);CHKERRQ(ierr);
290     ierr = VecViewFromOptions(u, NULL, "-initial_vec_view");CHKERRQ(ierr);
291     ierr = DMComputeL2Diff(dm, 0.0, user.exactFuncs, NULL, u, &error);CHKERRQ(ierr);
292     if (error < 1.0e-11) {ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial L_2 Error: < 1.0e-11\n");CHKERRQ(ierr);}
293     else                 {ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial L_2 Error: %g\n", error);CHKERRQ(ierr);}
294     ierr = SNESSolve(snes, NULL, u);CHKERRQ(ierr);
295     ierr = DMComputeL2Diff(dm, 0.0, user.exactFuncs, NULL, u, &error);CHKERRQ(ierr);
296     if (error < 1.0e-11) {ierr = PetscPrintf(PETSC_COMM_WORLD, "Final L_2 Error: < 1.0e-11\n");CHKERRQ(ierr);}
297     else                 {ierr = PetscPrintf(PETSC_COMM_WORLD, "Final L_2 Error: %g\n", error);CHKERRQ(ierr);}
298   }
299   ierr = VecViewFromOptions(u, NULL, "-sol_vec_view");CHKERRQ(ierr);
300 
301   ierr = VecDestroy(&u);CHKERRQ(ierr);
302   ierr = VecDestroy(&r);CHKERRQ(ierr);
303   ierr = SNESDestroy(&snes);CHKERRQ(ierr);
304   ierr = DMDestroy(&dm);CHKERRQ(ierr);
305   ierr = PetscFree(user.exactFuncs);CHKERRQ(ierr);
306   ierr = PetscFinalize();
307   return ierr;
308 }
309 
310 /*TEST
311 
312   build:
313     requires: !complex
314 
315   test:
316     suffix: 0
317     requires: triangle
318     args: -run_type test -dmsnes_check -potential_petscspace_degree 2 -conductivity_petscspace_degree 1 -multiplier_petscspace_degree 2
319 
320   test:
321     suffix: 1
322     requires: triangle
323     args: -potential_petscspace_degree 2 -conductivity_petscspace_degree 1 -multiplier_petscspace_degree 2 -snes_monitor -pc_type fieldsplit -pc_fieldsplit_0_fields 0,1 -pc_fieldsplit_1_fields 2 -pc_fieldsplit_type schur -pc_fieldsplit_schur_factorization_type full -pc_fieldsplit_schur_precondition selfp -fieldsplit_0_pc_type lu -fieldsplit_multiplier_ksp_rtol 1.0e-10 -fieldsplit_multiplier_pc_type lu -sol_vec_view
324 
325 TEST*/
326