Actual source code: ex11.c
1: static const char help[] = "Solves a Q1-P0 Stokes problem from Underworld.\n\
2: \n\
3: You can obtain a sample matrix from http://ftp.mcs.anl.gov/pub/petsc/Datafiles/matrices/underworld32.gz\n\
4: and run with -f underworld32.gz\n\n";
6: #include <petscksp.h>
7: #include <petscdmda.h>
9: static PetscErrorCode replace_submats(Mat A, IS isu, IS isp)
10: {
11: Mat A11,A22,A12,A21;
12: Mat nA11,nA22,nA12,nA21;
13: const char *prefix;
16: MatCreateSubMatrix(A,isu,isu,MAT_INITIAL_MATRIX,&A11);
17: MatCreateSubMatrix(A,isu,isp,MAT_INITIAL_MATRIX,&A12);
18: MatCreateSubMatrix(A,isp,isu,MAT_INITIAL_MATRIX,&A21);
19: MatCreateSubMatrix(A,isp,isp,MAT_INITIAL_MATRIX,&A22);
20: MatDuplicate(A11,MAT_COPY_VALUES,&nA11);
21: MatDuplicate(A12,MAT_COPY_VALUES,&nA12);
22: MatDuplicate(A21,MAT_COPY_VALUES,&nA21);
23: MatDuplicate(A22,MAT_COPY_VALUES,&nA22);
24: MatGetOptionsPrefix(A11,&prefix);
25: MatSetOptionsPrefix(nA11,prefix);
26: MatGetOptionsPrefix(A22,&prefix);
27: MatSetOptionsPrefix(nA22,prefix);
28: MatNestSetSubMat(A,0,0,nA11);
29: MatNestSetSubMat(A,0,1,nA12);
30: MatNestSetSubMat(A,1,0,nA21);
31: MatNestSetSubMat(A,1,1,nA22);
32: MatDestroy(&A11);
33: MatDestroy(&A12);
34: MatDestroy(&A21);
35: MatDestroy(&A22);
36: MatDestroy(&nA11);
37: MatDestroy(&nA12);
38: MatDestroy(&nA21);
39: MatDestroy(&nA22);
40: return 0;
41: }
43: PetscErrorCode LSCLoadTestOperators(Mat *A11,Mat *A12,Mat *A21,Mat *A22,Vec *b1,Vec *b2)
44: {
45: PetscViewer viewer;
46: char filename[PETSC_MAX_PATH_LEN];
47: PetscBool flg;
50: MatCreate(PETSC_COMM_WORLD,A11);
51: MatCreate(PETSC_COMM_WORLD,A12);
52: MatCreate(PETSC_COMM_WORLD,A21);
53: MatCreate(PETSC_COMM_WORLD,A22);
54: MatSetOptionsPrefix(*A11,"a11_");
55: MatSetOptionsPrefix(*A22,"a22_");
56: MatSetFromOptions(*A11);
57: MatSetFromOptions(*A22);
58: VecCreate(PETSC_COMM_WORLD,b1);
59: VecCreate(PETSC_COMM_WORLD,b2);
60: /* Load matrices from a Q1-P0 discretisation of variable viscosity Stokes. The matrix blocks are packed into one file. */
61: PetscOptionsGetString(NULL,NULL,"-f",filename,sizeof(filename),&flg);
63: PetscViewerBinaryOpen(PETSC_COMM_WORLD,filename,FILE_MODE_READ,&viewer);
64: MatLoad(*A11,viewer);
65: MatLoad(*A12,viewer);
66: MatLoad(*A21,viewer);
67: MatLoad(*A22,viewer);
68: VecLoad(*b1,viewer);
69: VecLoad(*b2,viewer);
70: PetscViewerDestroy(&viewer);
71: return 0;
72: }
74: PetscErrorCode LoadTestMatrices(Mat *_A,Vec *_x,Vec *_b,IS *_isu,IS *_isp)
75: {
76: Vec f,h,x,b,bX[2];
77: Mat A,Auu,Aup,Apu,App,bA[2][2];
78: IS is_u,is_p,bis[2];
79: PetscInt lnu,lnp,nu,np,i,start_u,end_u,start_p,end_p;
80: VecScatter *vscat;
81: PetscMPIInt rank;
84: /* fetch test matrices and vectors */
85: LSCLoadTestOperators(&Auu,&Aup,&Apu,&App,&f,&h);
87: /* build the mat-nest */
88: VecGetSize(f,&nu);
89: VecGetSize(h,&np);
91: VecGetLocalSize(f,&lnu);
92: VecGetLocalSize(h,&lnp);
94: VecGetOwnershipRange(f,&start_u,&end_u);
95: VecGetOwnershipRange(h,&start_p,&end_p);
97: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
98: PetscSynchronizedPrintf(PETSC_COMM_WORLD,"[%d] lnu = %D | lnp = %D \n", rank, lnu, lnp);
99: PetscSynchronizedPrintf(PETSC_COMM_WORLD,"[%d] s_u = %D | e_u = %D \n", rank, start_u, end_u);
100: PetscSynchronizedPrintf(PETSC_COMM_WORLD,"[%d] s_p = %D | e_p = %D \n", rank, start_p, end_p);
101: PetscSynchronizedPrintf(PETSC_COMM_WORLD,"[%d] is_u (offset) = %D \n", rank, start_u+start_p);
102: PetscSynchronizedPrintf(PETSC_COMM_WORLD,"[%d] is_p (offset) = %D \n", rank, start_u+start_p+lnu);
103: PetscSynchronizedFlush(PETSC_COMM_WORLD,PETSC_STDOUT);
105: ISCreateStride(PETSC_COMM_WORLD,lnu,start_u+start_p,1,&is_u);
106: ISCreateStride(PETSC_COMM_WORLD,lnp,start_u+start_p+lnu,1,&is_p);
108: bis[0] = is_u; bis[1] = is_p;
109: bA[0][0] = Auu; bA[0][1] = Aup;
110: bA[1][0] = Apu; bA[1][1] = App;
111: MatCreateNest(PETSC_COMM_WORLD,2,bis,2,bis,&bA[0][0],&A);
112: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
113: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
115: /* Pull f,h into b */
116: MatCreateVecs(A,&b,&x);
117: bX[0] = f; bX[1] = h;
118: PetscMalloc1(2,&vscat);
119: for (i=0; i<2; i++) {
120: VecScatterCreate(b,bis[i],bX[i],NULL,&vscat[i]);
121: VecScatterBegin(vscat[i],bX[i],b,INSERT_VALUES,SCATTER_REVERSE);
122: VecScatterEnd(vscat[i],bX[i],b,INSERT_VALUES,SCATTER_REVERSE);
123: VecScatterDestroy(&vscat[i]);
124: }
126: PetscFree(vscat);
127: MatDestroy(&Auu);
128: MatDestroy(&Aup);
129: MatDestroy(&Apu);
130: MatDestroy(&App);
131: VecDestroy(&f);
132: VecDestroy(&h);
134: *_isu = is_u;
135: *_isp = is_p;
136: *_A = A;
137: *_x = x;
138: *_b = b;
139: return 0;
140: }
142: PetscErrorCode port_lsd_bfbt(void)
143: {
144: Mat A,P;
145: Vec x,b;
146: KSP ksp_A;
147: PC pc_A;
148: IS isu,isp;
149: PetscBool test_fs = PETSC_FALSE;
152: LoadTestMatrices(&A,&x,&b,&isu,&isp);
153: PetscOptionsGetBool(NULL,NULL,"-test_fs",&test_fs,NULL);
154: if (!test_fs) {
155: PetscObjectReference((PetscObject)A);
156: P = A;
157: } else {
158: MatDuplicate(A,MAT_COPY_VALUES,&P);
159: }
160: KSPCreate(PETSC_COMM_WORLD,&ksp_A);
161: KSPSetOptionsPrefix(ksp_A,"fc_");
162: KSPSetOperators(ksp_A,A,P);
164: KSPSetFromOptions(ksp_A);
165: KSPGetPC(ksp_A,&pc_A);
166: PetscObjectTypeCompare((PetscObject)pc_A,PCLU,&test_fs);
167: if (test_fs) {
168: MatDestroy(&P);
169: MatConvert(A,MATAIJ,MAT_INITIAL_MATRIX,&P);
170: KSPSetOperators(ksp_A,A,P);
171: KSPSetFromOptions(ksp_A);
172: KSPSolve(ksp_A,b,x);
173: } else {
174: PCFieldSplitSetBlockSize(pc_A,2);
175: PCFieldSplitSetIS(pc_A,"velocity",isu);
176: PCFieldSplitSetIS(pc_A,"pressure",isp);
177: KSPSolve(ksp_A,b,x);
179: /* Pull u,p out of x */
180: {
181: PetscInt loc;
182: PetscReal max,norm;
183: PetscScalar sum;
184: Vec uvec,pvec;
185: VecScatter uscat,pscat;
186: Mat A11,A22;
188: /* grab matrices and create the compatable u,p vectors */
189: MatCreateSubMatrix(A,isu,isu,MAT_INITIAL_MATRIX,&A11);
190: MatCreateSubMatrix(A,isp,isp,MAT_INITIAL_MATRIX,&A22);
192: MatCreateVecs(A11,&uvec,NULL);
193: MatCreateVecs(A22,&pvec,NULL);
195: /* perform the scatter from x -> (u,p) */
196: VecScatterCreate(x,isu,uvec,NULL,&uscat);
197: VecScatterBegin(uscat,x,uvec,INSERT_VALUES,SCATTER_FORWARD);
198: VecScatterEnd(uscat,x,uvec,INSERT_VALUES,SCATTER_FORWARD);
200: VecScatterCreate(x,isp,pvec,NULL,&pscat);
201: VecScatterBegin(pscat,x,pvec,INSERT_VALUES,SCATTER_FORWARD);
202: VecScatterEnd(pscat,x,pvec,INSERT_VALUES,SCATTER_FORWARD);
204: PetscPrintf(PETSC_COMM_WORLD,"-- vector vector values --\n");
205: VecMin(uvec,&loc,&max);
206: PetscPrintf(PETSC_COMM_WORLD," Min(u) = %1.6f [loc=%D]\n",(double)max,loc);
207: VecMax(uvec,&loc,&max);
208: PetscPrintf(PETSC_COMM_WORLD," Max(u) = %1.6f [loc=%D]\n",(double)max,loc);
209: VecNorm(uvec,NORM_2,&norm);
210: PetscPrintf(PETSC_COMM_WORLD," Norm(u) = %1.6f \n",(double)norm);
211: VecSum(uvec,&sum);
212: PetscPrintf(PETSC_COMM_WORLD," Sum(u) = %1.6f \n",(double)PetscRealPart(sum));
214: PetscPrintf(PETSC_COMM_WORLD,"-- pressure vector values --\n");
215: VecMin(pvec,&loc,&max);
216: PetscPrintf(PETSC_COMM_WORLD," Min(p) = %1.6f [loc=%D]\n",(double)max,loc);
217: VecMax(pvec,&loc,&max);
218: PetscPrintf(PETSC_COMM_WORLD," Max(p) = %1.6f [loc=%D]\n",(double)max,loc);
219: VecNorm(pvec,NORM_2,&norm);
220: PetscPrintf(PETSC_COMM_WORLD," Norm(p) = %1.6f \n",(double)norm);
221: VecSum(pvec,&sum);
222: PetscPrintf(PETSC_COMM_WORLD," Sum(p) = %1.6f \n",(double)PetscRealPart(sum));
224: PetscPrintf(PETSC_COMM_WORLD,"-- Full vector values --\n");
225: VecMin(x,&loc,&max);
226: PetscPrintf(PETSC_COMM_WORLD," Min(u,p) = %1.6f [loc=%D]\n",(double)max,loc);
227: VecMax(x,&loc,&max);
228: PetscPrintf(PETSC_COMM_WORLD," Max(u,p) = %1.6f [loc=%D]\n",(double)max,loc);
229: VecNorm(x,NORM_2,&norm);
230: PetscPrintf(PETSC_COMM_WORLD," Norm(u,p) = %1.6f \n",(double)norm);
231: VecSum(x,&sum);
232: PetscPrintf(PETSC_COMM_WORLD," Sum(u,p) = %1.6f \n",(double)PetscRealPart(sum));
234: VecScatterDestroy(&uscat);
235: VecScatterDestroy(&pscat);
236: VecDestroy(&uvec);
237: VecDestroy(&pvec);
238: MatDestroy(&A11);
239: MatDestroy(&A22);
240: }
242: /* test second solve by changing the mat associated to the MATNEST blocks */
243: {
244: replace_submats(A,isu,isp);
245: replace_submats(P,isu,isp);
246: KSPSolve(ksp_A,b,x);
247: }
248: }
250: KSPDestroy(&ksp_A);
251: MatDestroy(&P);
252: MatDestroy(&A);
253: VecDestroy(&x);
254: VecDestroy(&b);
255: ISDestroy(&isu);
256: ISDestroy(&isp);
257: return 0;
258: }
260: int main(int argc,char **argv)
261: {
263: PetscInitialize(&argc,&argv,0,help);
264: port_lsd_bfbt();
265: PetscFinalize();
266: return 0;
267: }
269: /*TEST
271: test:
272: args: -f ${DATAFILESPATH}/matrices/underworld32.gz -fc_ksp_view -fc_ksp_monitor_short -fc_ksp_type fgmres -fc_ksp_max_it 4000 -fc_ksp_diagonal_scale -fc_pc_type fieldsplit -fc_pc_fieldsplit_type SCHUR -fc_pc_fieldsplit_schur_fact_type UPPER -fc_fieldsplit_velocity_ksp_type cg -fc_fieldsplit_velocity_pc_type cholesky -fc_fieldsplit_velocity_pc_factor_mat_ordering_type nd -fc_fieldsplit_pressure_ksp_max_it 100 -fc_fieldsplit_pressure_ksp_constant_null_space -fc_fieldsplit_pressure_ksp_monitor_short -fc_fieldsplit_pressure_pc_type lsc -fc_fieldsplit_pressure_lsc_ksp_type cg -fc_fieldsplit_pressure_lsc_ksp_max_it 100 -fc_fieldsplit_pressure_lsc_ksp_constant_null_space -fc_fieldsplit_pressure_lsc_ksp_converged_reason -fc_fieldsplit_pressure_lsc_pc_type icc -test_fs {{0 1}separate output} -fc_pc_fieldsplit_off_diag_use_amat {{0 1}separate output} -fc_pc_fieldsplit_diag_use_amat {{0 1}separate output}
273: requires: datafilespath double !complex !defined(PETSC_USE_64BIT_INDICES)
275: test:
276: suffix: 2
277: nsize: 4
278: args: -f ${DATAFILESPATH}/matrices/underworld32.gz -fc_ksp_view -fc_ksp_monitor_short -fc_ksp_type fgmres -fc_ksp_max_it 4000 -fc_ksp_diagonal_scale -fc_pc_type fieldsplit -fc_pc_fieldsplit_type SCHUR -fc_pc_fieldsplit_schur_fact_type UPPER -fc_fieldsplit_velocity_ksp_type cg -fc_fieldsplit_velocity_ksp_rtol 1.0e-6 -fc_fieldsplit_velocity_pc_type bjacobi -fc_fieldsplit_velocity_sub_pc_type cholesky -fc_fieldsplit_velocity_sub_pc_factor_mat_ordering_type nd -fc_fieldsplit_pressure_ksp_type fgmres -fc_fieldsplit_pressure_ksp_constant_null_space -fc_fieldsplit_pressure_ksp_monitor_short -fc_fieldsplit_pressure_pc_type lsc -fc_fieldsplit_pressure_lsc_ksp_type cg -fc_fieldsplit_pressure_lsc_ksp_rtol 1.0e-2 -fc_fieldsplit_pressure_lsc_ksp_constant_null_space -fc_fieldsplit_pressure_lsc_ksp_converged_reason -fc_fieldsplit_pressure_lsc_pc_type bjacobi -fc_fieldsplit_pressure_lsc_sub_pc_type icc -test_fs {{0 1}separate output} -fc_pc_fieldsplit_off_diag_use_amat {{0 1}separate output} -fc_pc_fieldsplit_diag_use_amat {{0 1}separate output}
279: requires: datafilespath double !complex !defined(PETSC_USE_64BIT_INDICES)
281: test:
282: suffix: 3
283: nsize: 2
284: args: -f ${DATAFILESPATH}/matrices/underworld32.gz -fc_ksp_view_pre -fc_pc_type lu
285: requires: datafilespath mumps double !complex !defined(PETSC_USE_64BIT_INDICES)
287: TEST*/