xref: /petsc/src/tao/tutorials/ex1.c (revision 2065540a855ff9f9c49aa4d22d544ff2b07d8a79)
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   PetscErrorCode ierr;
36 
37   PetscFunctionBeginUser;
38   options->runType = RUN_FULL;
39 
40   ierr = PetscOptionsBegin(comm, "", "Inverse Problem Options", "DMPLEX");CHKERRQ(ierr);
41   run  = options->runType;
42   ierr = PetscOptionsEList("-run_type", "The run type", "ex1.c", runTypes, 2, runTypes[options->runType], &run, NULL);CHKERRQ(ierr);
43   options->runType = (RunType) run;
44   ierr = PetscOptionsEnd();CHKERRQ(ierr);
45   PetscFunctionReturn(0);
46 }
47 
48 static PetscErrorCode CreateMesh(MPI_Comm comm, AppCtx *user, DM *dm)
49 {
50   DM             distributedMesh = NULL;
51   PetscErrorCode ierr;
52 
53   PetscFunctionBeginUser;
54   ierr = DMPlexCreateBoxMesh(comm, 2, PETSC_TRUE, NULL, NULL, NULL, NULL, PETSC_TRUE, dm);CHKERRQ(ierr);
55   ierr = PetscObjectSetName((PetscObject) *dm, "Mesh");CHKERRQ(ierr);
56   ierr = DMPlexDistribute(*dm, 0, NULL, &distributedMesh);CHKERRQ(ierr);
57   if (distributedMesh) {
58     ierr = DMDestroy(dm);CHKERRQ(ierr);
59     *dm  = distributedMesh;
60   }
61   ierr = DMSetFromOptions(*dm);CHKERRQ(ierr);
62   ierr = DMViewFromOptions(*dm, NULL, "-dm_view");CHKERRQ(ierr);
63   PetscFunctionReturn(0);
64 }
65 
66 /* u - (x^2 + y^2) */
67 void f0_u(PetscInt dim, PetscInt Nf, PetscInt NfAux,
68           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
69           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
70           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
71 {
72   f0[0] = u[0] - (x[0]*x[0] + x[1]*x[1]);
73 }
74 /* a \nabla\lambda */
75 void f1_u(PetscInt dim, PetscInt Nf, PetscInt NfAux,
76           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
77           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
78           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f1[])
79 {
80   PetscInt d;
81   for (d = 0; d < dim; ++d) f1[d] = u[1]*u_x[dim*2+d];
82 }
83 /* I */
84 void g0_uu(PetscInt dim, PetscInt Nf, PetscInt NfAux,
85            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
86            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
87            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g0[])
88 {
89   g0[0] = 1.0;
90 }
91 /* \nabla */
92 void g2_ua(PetscInt dim, PetscInt Nf, PetscInt NfAux,
93            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
94            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
95            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g2[])
96 {
97   PetscInt d;
98   for (d = 0; d < dim; ++d) g2[d] = u_x[dim*2+d];
99 }
100 /* a */
101 void g3_ul(PetscInt dim, PetscInt Nf, PetscInt NfAux,
102            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
103            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
104            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g3[])
105 {
106   PetscInt d;
107   for (d = 0; d < dim; ++d) g3[d*dim+d] = u[1];
108 }
109 /* a - (x + y) */
110 void f0_a(PetscInt dim, PetscInt Nf, PetscInt NfAux,
111           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
112           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
113           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
114 {
115   f0[0] = u[1] - (x[0] + x[1]);
116 }
117 /* \lambda \nabla u */
118 void f1_a(PetscInt dim, PetscInt Nf, PetscInt NfAux,
119           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
120           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
121           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f1[])
122 {
123   PetscInt d;
124   for (d = 0; d < dim; ++d) f1[d] = u[2]*u_x[d];
125 }
126 /* I */
127 void g0_aa(PetscInt dim, PetscInt Nf, PetscInt NfAux,
128            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
129            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
130            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g0[])
131 {
132   g0[0] = 1.0;
133 }
134 /* 6 (x + y) */
135 void f0_l(PetscInt dim, PetscInt Nf, PetscInt NfAux,
136           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
137           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
138           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
139 {
140   f0[0] = 6.0*(x[0] + x[1]);
141 }
142 /* a \nabla u */
143 void f1_l(PetscInt dim, PetscInt Nf, PetscInt NfAux,
144           const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
145           const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
146           PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f1[])
147 {
148   PetscInt d;
149   for (d = 0; d < dim; ++d) f1[d] = u[1]*u_x[d];
150 }
151 /* \nabla u */
152 void g2_la(PetscInt dim, PetscInt Nf, PetscInt NfAux,
153            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
154            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
155            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g2[])
156 {
157   PetscInt d;
158   for (d = 0; d < dim; ++d) g2[d] = u_x[d];
159 }
160 /* a */
161 void g3_lu(PetscInt dim, PetscInt Nf, PetscInt NfAux,
162            const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
163            const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
164            PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g3[])
165 {
166   PetscInt d;
167   for (d = 0; d < dim; ++d) g3[d*dim+d] = u[1];
168 }
169 
170 /*
171   In 2D for Dirichlet conditions with a variable coefficient, we use exact solution:
172 
173     u  = x^2 + y^2
174     f  = 6 (x + y)
175     kappa(a) = a = (x + y)
176 
177   so that
178 
179     -\div \kappa(a) \grad u + f = -6 (x + y) + 6 (x + y) = 0
180 */
181 PetscErrorCode quadratic_u_2d(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *u, void *ctx)
182 {
183   *u = x[0]*x[0] + x[1]*x[1];
184   return 0;
185 }
186 PetscErrorCode linear_a_2d(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *a, void *ctx)
187 {
188   *a = x[0] + x[1];
189   return 0;
190 }
191 PetscErrorCode zero(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *l, void *ctx)
192 {
193   *l = 0.0;
194   return 0;
195 }
196 
197 PetscErrorCode SetupProblem(DM dm, AppCtx *user)
198 {
199   PetscDS        ds;
200   DMLabel        label;
201   const PetscInt id = 1;
202   PetscErrorCode ierr;
203 
204   PetscFunctionBeginUser;
205   ierr = DMGetDS(dm, &ds);CHKERRQ(ierr);
206   ierr = PetscDSSetResidual(ds, 0, f0_u, f1_u);CHKERRQ(ierr);
207   ierr = PetscDSSetResidual(ds, 1, f0_a, f1_a);CHKERRQ(ierr);
208   ierr = PetscDSSetResidual(ds, 2, f0_l, f1_l);CHKERRQ(ierr);
209   ierr = PetscDSSetJacobian(ds, 0, 0, g0_uu, NULL, NULL, NULL);CHKERRQ(ierr);
210   ierr = PetscDSSetJacobian(ds, 0, 1, NULL, NULL, g2_ua, NULL);CHKERRQ(ierr);
211   ierr = PetscDSSetJacobian(ds, 0, 2, NULL, NULL, NULL, g3_ul);CHKERRQ(ierr);
212   ierr = PetscDSSetJacobian(ds, 1, 1, g0_aa, NULL, NULL, NULL);CHKERRQ(ierr);
213   ierr = PetscDSSetJacobian(ds, 2, 1, NULL, NULL, g2_la, NULL);CHKERRQ(ierr);
214   ierr = PetscDSSetJacobian(ds, 2, 0, NULL, NULL, NULL, g3_lu);CHKERRQ(ierr);
215 
216   ierr = PetscDSSetExactSolution(ds, 0, quadratic_u_2d, NULL);CHKERRQ(ierr);
217   ierr = PetscDSSetExactSolution(ds, 1, linear_a_2d, NULL);CHKERRQ(ierr);
218   ierr = PetscDSSetExactSolution(ds, 2, zero, NULL);CHKERRQ(ierr);
219   ierr = DMGetLabel(dm, "marker", &label);CHKERRQ(ierr);
220   ierr = DMAddBoundary(dm, DM_BC_ESSENTIAL, "wall", label, 1, &id, 0, 0, NULL, (void (*)(void)) quadratic_u_2d, NULL, user, NULL);CHKERRQ(ierr);
221   ierr = DMAddBoundary(dm, DM_BC_ESSENTIAL, "wall", label, 1, &id, 1, 0, NULL, (void (*)(void)) linear_a_2d, NULL, user, NULL);CHKERRQ(ierr);
222   ierr = DMAddBoundary(dm, DM_BC_ESSENTIAL, "wall", label, 1, &id, 2, 0, NULL, (void (*)(void)) zero, NULL, user, NULL);CHKERRQ(ierr);
223   PetscFunctionReturn(0);
224 }
225 
226 PetscErrorCode SetupDiscretization(DM dm, AppCtx *user)
227 {
228   DM              cdm = dm;
229   const PetscInt  dim = 2;
230   PetscFE         fe[3];
231   PetscInt        f;
232   MPI_Comm        comm;
233   PetscErrorCode  ierr;
234 
235   PetscFunctionBeginUser;
236   /* Create finite element */
237   ierr = PetscObjectGetComm((PetscObject) dm, &comm);CHKERRQ(ierr);
238   ierr = PetscFECreateDefault(comm, dim, 1, PETSC_TRUE, "potential_", -1, &fe[0]);CHKERRQ(ierr);
239   ierr = PetscObjectSetName((PetscObject) fe[0], "potential");CHKERRQ(ierr);
240   ierr = PetscFECreateDefault(comm, dim, 1, PETSC_TRUE, "conductivity_", -1, &fe[1]);CHKERRQ(ierr);
241   ierr = PetscObjectSetName((PetscObject) fe[1], "conductivity");CHKERRQ(ierr);
242   ierr = PetscFECopyQuadrature(fe[0], fe[1]);CHKERRQ(ierr);
243   ierr = PetscFECreateDefault(comm, dim, 1, PETSC_TRUE, "multiplier_", -1, &fe[2]);CHKERRQ(ierr);
244   ierr = PetscObjectSetName((PetscObject) fe[2], "multiplier");CHKERRQ(ierr);
245   ierr = PetscFECopyQuadrature(fe[0], fe[2]);CHKERRQ(ierr);
246   /* Set discretization and boundary conditions for each mesh */
247   for (f = 0; f < 3; ++f) {ierr = DMSetField(dm, f, NULL, (PetscObject) fe[f]);CHKERRQ(ierr);}
248   ierr = DMCreateDS(dm);CHKERRQ(ierr);
249   ierr = SetupProblem(dm, user);CHKERRQ(ierr);
250   while (cdm) {
251     ierr = DMCopyDisc(dm, cdm);CHKERRQ(ierr);
252     ierr = DMGetCoarseDM(cdm, &cdm);CHKERRQ(ierr);
253   }
254   for (f = 0; f < 3; ++f) {ierr = PetscFEDestroy(&fe[f]);CHKERRQ(ierr);}
255   PetscFunctionReturn(0);
256 }
257 
258 int main(int argc, char **argv)
259 {
260   DM             dm;
261   SNES           snes;
262   Vec            u, r;
263   AppCtx         user;
264   PetscErrorCode ierr;
265 
266   ierr = PetscInitialize(&argc, &argv, NULL,help);if (ierr) return ierr;
267   ierr = ProcessOptions(PETSC_COMM_WORLD, &user);CHKERRQ(ierr);
268   ierr = SNESCreate(PETSC_COMM_WORLD, &snes);CHKERRQ(ierr);
269   ierr = CreateMesh(PETSC_COMM_WORLD, &user, &dm);CHKERRQ(ierr);
270   ierr = SNESSetDM(snes, dm);CHKERRQ(ierr);
271   ierr = SetupDiscretization(dm, &user);CHKERRQ(ierr);
272 
273   ierr = DMCreateGlobalVector(dm, &u);CHKERRQ(ierr);
274   ierr = PetscObjectSetName((PetscObject) u, "solution");CHKERRQ(ierr);
275   ierr = VecDuplicate(u, &r);CHKERRQ(ierr);
276   ierr = DMPlexSetSNESLocalFEM(dm,&user,&user,&user);CHKERRQ(ierr);
277   ierr = SNESSetFromOptions(snes);CHKERRQ(ierr);
278 
279   ierr = DMSNESCheckFromOptions(snes, u);CHKERRQ(ierr);
280   if (user.runType == RUN_FULL) {
281     PetscDS          ds;
282     PetscErrorCode (*exactFuncs[3])(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar *u, void *ctx);
283     PetscErrorCode (*initialGuess[3])(PetscInt dim, PetscReal t, const PetscReal x[], PetscInt Nf, PetscScalar u[], void *ctx);
284     PetscReal        error;
285 
286     ierr = DMGetDS(dm, &ds);CHKERRQ(ierr);
287     ierr = PetscDSGetExactSolution(ds, 0, &exactFuncs[0], NULL);CHKERRQ(ierr);
288     ierr = PetscDSGetExactSolution(ds, 1, &exactFuncs[1], NULL);CHKERRQ(ierr);
289     ierr = PetscDSGetExactSolution(ds, 2, &exactFuncs[2], NULL);CHKERRQ(ierr);
290     initialGuess[0] = zero;
291     initialGuess[1] = zero;
292     initialGuess[2] = zero;
293     ierr = DMProjectFunction(dm, 0.0, initialGuess, NULL, INSERT_VALUES, u);CHKERRQ(ierr);
294     ierr = VecViewFromOptions(u, NULL, "-initial_vec_view");CHKERRQ(ierr);
295     ierr = DMComputeL2Diff(dm, 0.0, exactFuncs, NULL, u, &error);CHKERRQ(ierr);
296     if (error < 1.0e-11) {ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial L_2 Error: < 1.0e-11\n");CHKERRQ(ierr);}
297     else                 {ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial L_2 Error: %g\n", error);CHKERRQ(ierr);}
298     ierr = SNESSolve(snes, NULL, u);CHKERRQ(ierr);
299     ierr = DMComputeL2Diff(dm, 0.0, exactFuncs, NULL, u, &error);CHKERRQ(ierr);
300     if (error < 1.0e-11) {ierr = PetscPrintf(PETSC_COMM_WORLD, "Final L_2 Error: < 1.0e-11\n");CHKERRQ(ierr);}
301     else                 {ierr = PetscPrintf(PETSC_COMM_WORLD, "Final L_2 Error: %g\n", error);CHKERRQ(ierr);}
302   }
303   ierr = VecViewFromOptions(u, NULL, "-sol_vec_view");CHKERRQ(ierr);
304 
305   ierr = VecDestroy(&u);CHKERRQ(ierr);
306   ierr = VecDestroy(&r);CHKERRQ(ierr);
307   ierr = SNESDestroy(&snes);CHKERRQ(ierr);
308   ierr = DMDestroy(&dm);CHKERRQ(ierr);
309   ierr = PetscFinalize();
310   return ierr;
311 }
312 
313 /*TEST
314 
315   build:
316     requires: !complex
317 
318   test:
319     suffix: 0
320     requires: triangle
321     args: -run_type test -dmsnes_check -potential_petscspace_degree 2 -conductivity_petscspace_degree 1 -multiplier_petscspace_degree 2
322 
323   test:
324     suffix: 1
325     requires: triangle
326     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
327 
328 TEST*/
329