xref: /petsc/src/tao/tutorials/ex1.c (revision f97672e55eacc8688507b9471cd7ec2664d7f203)
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 } AppCtx;
30 
31 static PetscErrorCode ProcessOptions(MPI_Comm comm, AppCtx *options)
32 {
33   const char    *runTypes[2] = {"full", "test"};
34   PetscInt       run;
35 
36   PetscFunctionBeginUser;
37   options->runType = RUN_FULL;
38   PetscOptionsBegin(comm, "", "Inverse Problem Options", "DMPLEX");
39   run  = options->runType;
40   PetscCall(PetscOptionsEList("-run_type", "The run type", "ex1.c", runTypes, 2, runTypes[options->runType], &run, NULL));
41   options->runType = (RunType) run;
42   PetscOptionsEnd();
43   PetscFunctionReturn(0);
44 }
45 
46 static PetscErrorCode CreateMesh(MPI_Comm comm, AppCtx *user, DM *dm)
47 {
48   PetscFunctionBeginUser;
49   PetscCall(DMCreate(comm, dm));
50   PetscCall(DMSetType(*dm, DMPLEX));
51   PetscCall(DMSetFromOptions(*dm));
52   PetscCall(DMViewFromOptions(*dm, NULL, "-dm_view"));
53   PetscFunctionReturn(0);
54 }
55 
56 /* u - (x^2 + y^2) */
57 void f0_u(PetscInt dim, PetscInt Nf, PetscInt NfAux,
58           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
59           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
60           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
61 {
62   f0[0] = u[0] - (x[0]*x[0] + x[1]*x[1]);
63 }
64 /* a \nabla\lambda */
65 void f1_u(PetscInt dim, PetscInt Nf, PetscInt NfAux,
66           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
67           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
68           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f1[])
69 {
70   PetscInt d;
71   for (d = 0; d < dim; ++d) f1[d] = u[1]*u_x[dim*2+d];
72 }
73 /* I */
74 void g0_uu(PetscInt dim, PetscInt Nf, PetscInt NfAux,
75            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
76            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
77            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g0[])
78 {
79   g0[0] = 1.0;
80 }
81 /* \nabla */
82 void g2_ua(PetscInt dim, PetscInt Nf, PetscInt NfAux,
83            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
84            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
85            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g2[])
86 {
87   PetscInt d;
88   for (d = 0; d < dim; ++d) g2[d] = u_x[dim*2+d];
89 }
90 /* a */
91 void g3_ul(PetscInt dim, PetscInt Nf, PetscInt NfAux,
92            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
93            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
94            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g3[])
95 {
96   PetscInt d;
97   for (d = 0; d < dim; ++d) g3[d*dim+d] = u[1];
98 }
99 /* a - (x + y) */
100 void f0_a(PetscInt dim, PetscInt Nf, PetscInt NfAux,
101           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
102           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
103           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
104 {
105   f0[0] = u[1] - (x[0] + x[1]);
106 }
107 /* \lambda \nabla u */
108 void f1_a(PetscInt dim, PetscInt Nf, PetscInt NfAux,
109           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
110           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
111           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f1[])
112 {
113   PetscInt d;
114   for (d = 0; d < dim; ++d) f1[d] = u[2]*u_x[d];
115 }
116 /* I */
117 void g0_aa(PetscInt dim, PetscInt Nf, PetscInt NfAux,
118            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
119            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
120            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g0[])
121 {
122   g0[0] = 1.0;
123 }
124 /* 6 (x + y) */
125 void f0_l(PetscInt dim, PetscInt Nf, PetscInt NfAux,
126           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
127           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
128           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
129 {
130   f0[0] = 6.0*(x[0] + x[1]);
131 }
132 /* a \nabla u */
133 void f1_l(PetscInt dim, PetscInt Nf, PetscInt NfAux,
134           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
135           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
136           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f1[])
137 {
138   PetscInt d;
139   for (d = 0; d < dim; ++d) f1[d] = u[1]*u_x[d];
140 }
141 /* \nabla u */
142 void g2_la(PetscInt dim, PetscInt Nf, PetscInt NfAux,
143            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
144            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
145            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g2[])
146 {
147   PetscInt d;
148   for (d = 0; d < dim; ++d) g2[d] = u_x[d];
149 }
150 /* a */
151 void g3_lu(PetscInt dim, PetscInt Nf, PetscInt NfAux,
152            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
153            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
154            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g3[])
155 {
156   PetscInt d;
157   for (d = 0; d < dim; ++d) g3[d*dim+d] = u[1];
158 }
159 
160 /*
161   In 2D for Dirichlet conditions with a variable coefficient, we use exact solution:
162 
163     u  = x^2 + y^2
164     f  = 6 (x + y)
165     kappa(a) = a = (x + y)
166 
167   so that
168 
169     -\div \kappa(a) \grad u + f = -6 (x + y) + 6 (x + y) = 0
170 */
171 PetscErrorCode quadratic_u_2d(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *u, void *ctx)
172 {
173   *u = x[0]*x[0] + x[1]*x[1];
174   return 0;
175 }
176 PetscErrorCode linear_a_2d(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *a, void *ctx)
177 {
178   *a = x[0] + x[1];
179   return 0;
180 }
181 PetscErrorCode zero(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *l, void *ctx)
182 {
183   *l = 0.0;
184   return 0;
185 }
186 
187 PetscErrorCode SetupProblem(DM dm, AppCtx *user)
188 {
189   PetscDS        ds;
190   DMLabel        label;
191   const PetscInt id = 1;
192 
193   PetscFunctionBeginUser;
194   PetscCall(DMGetDS(dm, &ds));
195   PetscCall(PetscDSSetResidual(ds, 0, f0_u, f1_u));
196   PetscCall(PetscDSSetResidual(ds, 1, f0_a, f1_a));
197   PetscCall(PetscDSSetResidual(ds, 2, f0_l, f1_l));
198   PetscCall(PetscDSSetJacobian(ds, 0, 0, g0_uu, NULL, NULL, NULL));
199   PetscCall(PetscDSSetJacobian(ds, 0, 1, NULL, NULL, g2_ua, NULL));
200   PetscCall(PetscDSSetJacobian(ds, 0, 2, NULL, NULL, NULL, g3_ul));
201   PetscCall(PetscDSSetJacobian(ds, 1, 1, g0_aa, NULL, NULL, NULL));
202   PetscCall(PetscDSSetJacobian(ds, 2, 1, NULL, NULL, g2_la, NULL));
203   PetscCall(PetscDSSetJacobian(ds, 2, 0, NULL, NULL, NULL, g3_lu));
204 
205   PetscCall(PetscDSSetExactSolution(ds, 0, quadratic_u_2d, NULL));
206   PetscCall(PetscDSSetExactSolution(ds, 1, linear_a_2d, NULL));
207   PetscCall(PetscDSSetExactSolution(ds, 2, zero, NULL));
208   PetscCall(DMGetLabel(dm, "marker", &label));
209   PetscCall(DMAddBoundary(dm, DM_BC_ESSENTIAL, "wall", label, 1, &id, 0, 0, NULL, (void (*)(void)) quadratic_u_2d, NULL, user, NULL));
210   PetscCall(DMAddBoundary(dm, DM_BC_ESSENTIAL, "wall", label, 1, &id, 1, 0, NULL, (void (*)(void)) linear_a_2d, NULL, user, NULL));
211   PetscCall(DMAddBoundary(dm, DM_BC_ESSENTIAL, "wall", label, 1, &id, 2, 0, NULL, (void (*)(void)) zero, NULL, user, NULL));
212   PetscFunctionReturn(0);
213 }
214 
215 PetscErrorCode SetupDiscretization(DM dm, AppCtx *user)
216 {
217   DM              cdm = dm;
218   const PetscInt  dim = 2;
219   PetscFE         fe[3];
220   PetscInt        f;
221   MPI_Comm        comm;
222 
223   PetscFunctionBeginUser;
224   /* Create finite element */
225   PetscCall(PetscObjectGetComm((PetscObject) dm, &comm));
226   PetscCall(PetscFECreateDefault(comm, dim, 1, PETSC_TRUE, "potential_", -1, &fe[0]));
227   PetscCall(PetscObjectSetName((PetscObject) fe[0], "potential"));
228   PetscCall(PetscFECreateDefault(comm, dim, 1, PETSC_TRUE, "conductivity_", -1, &fe[1]));
229   PetscCall(PetscObjectSetName((PetscObject) fe[1], "conductivity"));
230   PetscCall(PetscFECopyQuadrature(fe[0], fe[1]));
231   PetscCall(PetscFECreateDefault(comm, dim, 1, PETSC_TRUE, "multiplier_", -1, &fe[2]));
232   PetscCall(PetscObjectSetName((PetscObject) fe[2], "multiplier"));
233   PetscCall(PetscFECopyQuadrature(fe[0], fe[2]));
234   /* Set discretization and boundary conditions for each mesh */
235   for (f = 0; f < 3; ++f) PetscCall(DMSetField(dm, f, NULL, (PetscObject) fe[f]));
236   PetscCall(DMCreateDS(dm));
237   PetscCall(SetupProblem(dm, user));
238   while (cdm) {
239     PetscCall(DMCopyDisc(dm, cdm));
240     PetscCall(DMGetCoarseDM(cdm, &cdm));
241   }
242   for (f = 0; f < 3; ++f) PetscCall(PetscFEDestroy(&fe[f]));
243   PetscFunctionReturn(0);
244 }
245 
246 int main(int argc, char **argv)
247 {
248   DM             dm;
249   SNES           snes;
250   Vec            u, r;
251   AppCtx         user;
252 
253   PetscCall(PetscInitialize(&argc, &argv, NULL,help));
254   PetscCall(ProcessOptions(PETSC_COMM_WORLD, &user));
255   PetscCall(SNESCreate(PETSC_COMM_WORLD, &snes));
256   PetscCall(CreateMesh(PETSC_COMM_WORLD, &user, &dm));
257   PetscCall(SNESSetDM(snes, dm));
258   PetscCall(SetupDiscretization(dm, &user));
259 
260   PetscCall(DMCreateGlobalVector(dm, &u));
261   PetscCall(PetscObjectSetName((PetscObject) u, "solution"));
262   PetscCall(VecDuplicate(u, &r));
263   PetscCall(DMPlexSetSNESLocalFEM(dm,&user,&user,&user));
264   PetscCall(SNESSetFromOptions(snes));
265 
266   PetscCall(DMSNESCheckFromOptions(snes, u));
267   if (user.runType == RUN_FULL) {
268     PetscDS          ds;
269     PetscErrorCode (*exactFuncs[3])(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *u, void *ctx);
270     PetscErrorCode (*initialGuess[3])(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar u[], void *ctx);
271     PetscReal        error;
272 
273     PetscCall(DMGetDS(dm, &ds));
274     PetscCall(PetscDSGetExactSolution(ds, 0, &exactFuncs[0], NULL));
275     PetscCall(PetscDSGetExactSolution(ds, 1, &exactFuncs[1], NULL));
276     PetscCall(PetscDSGetExactSolution(ds, 2, &exactFuncs[2], NULL));
277     initialGuess[0] = zero;
278     initialGuess[1] = zero;
279     initialGuess[2] = zero;
280     PetscCall(DMProjectFunction(dm, 0.0, initialGuess, NULL, INSERT_VALUES, u));
281     PetscCall(VecViewFromOptions(u, NULL, "-initial_vec_view"));
282     PetscCall(DMComputeL2Diff(dm, 0.0, exactFuncs, NULL, u, &error));
283     if (error < 1.0e-11) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Initial L_2 Error: < 1.0e-11\n"));
284     else                 PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Initial L_2 Error: %g\n", (double)error));
285     PetscCall(SNESSolve(snes, NULL, u));
286     PetscCall(DMComputeL2Diff(dm, 0.0, exactFuncs, NULL, u, &error));
287     if (error < 1.0e-11) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Final L_2 Error: < 1.0e-11\n"));
288     else                 PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Final L_2 Error: %g\n", (double)error));
289   }
290   PetscCall(VecViewFromOptions(u, NULL, "-sol_vec_view"));
291 
292   PetscCall(VecDestroy(&u));
293   PetscCall(VecDestroy(&r));
294   PetscCall(SNESDestroy(&snes));
295   PetscCall(DMDestroy(&dm));
296   PetscCall(PetscFinalize());
297   return 0;
298 }
299 
300 /*TEST
301 
302   build:
303     requires: !complex
304 
305   test:
306     suffix: 0
307     requires: triangle
308     args: -run_type test -dmsnes_check -potential_petscspace_degree 2 -conductivity_petscspace_degree 1 -multiplier_petscspace_degree 2
309 
310   test:
311     suffix: 1
312     requires: triangle
313     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
314 
315 TEST*/
316