Actual source code: ex6.c

  1: static char help[] = "Reads a PETSc matrix and vector from a file and solves a linear system.\n\
  2: Input arguments are:\n\
  3:   -f <input_file> : file to load. For example see $PETSC_DIR/share/petsc/datafiles/matrices\n\n";

  5: #include <petscksp.h>
  6: #include <petsclog.h>

  8: static PetscErrorCode KSPTestResidualMonitor(KSP ksp, PetscInt i, PetscReal r, void *ctx)
  9: {
 10:   Vec      *t, *v;
 11:   PetscReal err;

 13:   PetscFunctionBeginUser;
 14:   PetscCall(KSPCreateVecs(ksp, 2, &t, 2, &v));
 15:   PetscCall(KSPBuildResidualDefault(ksp, t[0], v[0], &v[0]));
 16:   PetscCall(KSPBuildResidual(ksp, t[1], v[1], &v[1]));
 17:   PetscCall(VecAXPY(v[1], -1.0, v[0]));
 18:   PetscCall(VecNorm(v[1], NORM_INFINITY, &err));
 19:   PetscCheck(err <= PETSC_SMALL, PetscObjectComm((PetscObject)ksp), PETSC_ERR_PLIB, "Inconsistent residual computed at step %" PetscInt_FMT ": %g (KSP %g)", i, (double)err, (double)r);
 20:   PetscCall(VecDestroyVecs(2, &t));
 21:   PetscCall(VecDestroyVecs(2, &v));
 22:   PetscFunctionReturn(PETSC_SUCCESS);
 23: }

 25: int main(int argc, char **args)
 26: {
 27:   PetscInt      its;
 28:   PetscLogStage stage1, stage2;
 29:   PetscReal     norm;
 30:   Vec           x, b, u;
 31:   Mat           A;
 32:   char          file[PETSC_MAX_PATH_LEN];
 33:   PetscViewer   fd;
 34:   PetscBool     table = PETSC_FALSE, flg, test_residual = PETSC_FALSE, b_in_f = PETSC_TRUE;
 35:   KSP           ksp;

 37:   PetscFunctionBeginUser;
 38:   PetscCall(PetscInitialize(&argc, &args, NULL, help));
 39:   PetscCall(PetscOptionsGetBool(NULL, NULL, "-table", &table, NULL));
 40:   PetscCall(PetscOptionsGetBool(NULL, NULL, "-test_residual", &test_residual, NULL));
 41:   PetscCall(PetscOptionsGetBool(NULL, NULL, "-b_in_f", &b_in_f, NULL));

 43:   /* Read matrix and RHS */
 44:   PetscCall(PetscOptionsGetString(NULL, NULL, "-f", file, sizeof(file), &flg));
 45:   PetscCheck(flg, PETSC_COMM_WORLD, PETSC_ERR_USER_INPUT, "Must indicate binary file with the -f option");
 46:   PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD, file, FILE_MODE_READ, &fd));
 47:   PetscCall(MatCreate(PETSC_COMM_WORLD, &A));
 48:   PetscCall(MatLoad(A, fd));
 49:   if (b_in_f) {
 50:     PetscCall(VecCreate(PETSC_COMM_WORLD, &b));
 51:     PetscCall(VecLoad(b, fd));
 52:   } else {
 53:     PetscCall(MatCreateVecs(A, NULL, &b));
 54:     PetscCall(VecSetRandom(b, NULL));
 55:   }
 56:   PetscCall(PetscViewerDestroy(&fd));

 58:   /*
 59:    If the load matrix is larger then the vector, due to being padded
 60:    to match the blocksize then create a new padded vector
 61:   */
 62:   {
 63:     PetscInt     m, n, j, mvec, start, end, indx;
 64:     Vec          tmp;
 65:     PetscScalar *bold;

 67:     PetscCall(MatGetLocalSize(A, &m, &n));
 68:     PetscCall(VecCreate(PETSC_COMM_WORLD, &tmp));
 69:     PetscCall(VecSetSizes(tmp, m, PETSC_DECIDE));
 70:     PetscCall(VecSetFromOptions(tmp));
 71:     PetscCall(VecGetOwnershipRange(b, &start, &end));
 72:     PetscCall(VecGetLocalSize(b, &mvec));
 73:     PetscCall(VecGetArray(b, &bold));
 74:     for (j = 0; j < mvec; j++) {
 75:       indx = start + j;
 76:       PetscCall(VecSetValues(tmp, 1, &indx, bold + j, INSERT_VALUES));
 77:     }
 78:     PetscCall(VecRestoreArray(b, &bold));
 79:     PetscCall(VecDestroy(&b));
 80:     PetscCall(VecAssemblyBegin(tmp));
 81:     PetscCall(VecAssemblyEnd(tmp));
 82:     b = tmp;
 83:   }
 84:   PetscCall(VecDuplicate(b, &x));
 85:   PetscCall(VecDuplicate(b, &u));

 87:   PetscCall(VecSet(x, 0.0));
 88:   PetscCall(PetscBarrier((PetscObject)A));

 90:   PetscCall(PetscLogStageRegister("mystage 1", &stage1));
 91:   PetscCall(PetscLogStagePush(stage1));
 92:   PetscCall(KSPCreate(PETSC_COMM_WORLD, &ksp));
 93:   PetscCall(KSPSetOperators(ksp, A, A));
 94:   PetscCall(KSPSetFromOptions(ksp));
 95:   if (test_residual) PetscCall(KSPMonitorSet(ksp, KSPTestResidualMonitor, NULL, NULL));
 96:   PetscCall(KSPSetUp(ksp));
 97:   PetscCall(KSPSetUpOnBlocks(ksp));
 98:   PetscCall(PetscLogStagePop());
 99:   PetscCall(PetscBarrier((PetscObject)A));

101:   PetscCall(PetscLogStageRegister("mystage 2", &stage2));
102:   PetscCall(PetscLogStagePush(stage2));
103:   PetscCall(KSPSolve(ksp, b, x));
104:   PetscCall(PetscLogStagePop());

106:   /* Show result */
107:   PetscCall(MatMult(A, x, u));
108:   PetscCall(VecAXPY(u, -1.0, b));
109:   PetscCall(VecNorm(u, NORM_2, &norm));
110:   PetscCall(KSPGetIterationNumber(ksp, &its));
111:   /*  matrix PC   KSP   Options       its    residual  */
112:   if (table) {
113:     char       *matrixname, kspinfo[120];
114:     PetscViewer viewer;
115:     PetscCall(PetscViewerStringOpen(PETSC_COMM_WORLD, kspinfo, sizeof(kspinfo), &viewer));
116:     PetscCall(KSPView(ksp, viewer));
117:     PetscCall(PetscStrrchr(file, '/', &matrixname));
118:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "%-8.8s %3" PetscInt_FMT " %2.0e %s \n", matrixname, its, (double)norm, kspinfo));
119:     PetscCall(PetscViewerDestroy(&viewer));
120:   } else {
121:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Number of iterations = %3" PetscInt_FMT "\n", its));
122:     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Residual norm = %g\n", (double)norm));
123:   }

125:   /* Cleanup */
126:   PetscCall(KSPDestroy(&ksp));
127:   PetscCall(VecDestroy(&x));
128:   PetscCall(VecDestroy(&b));
129:   PetscCall(VecDestroy(&u));
130:   PetscCall(MatDestroy(&A));
131:   PetscCall(PetscFinalize());
132:   return 0;
133: }

135: /*TEST

137:     test:
138:       args: -ksp_type preonly -pc_type lu -options_left no -f ${DATAFILESPATH}/matrices/arco1
139:       requires: datafilespath double !complex !defined(PETSC_USE_64BIT_INDICES)

141:     test:
142:       suffix: 2
143:       args: -sub_pc_type ilu -options_left no -f ${DATAFILESPATH}/matrices/arco1 -ksp_gmres_restart 100 -ksp_gmres_cgs_refinement_type refine_always -sub_ksp_type preonly -pc_type bjacobi -pc_bjacobi_blocks 8 -sub_pc_factor_in_place -ksp_monitor_short
144:       requires: datafilespath double !complex !defined(PETSC_USE_64BIT_INDICES)

146:     test:
147:       suffix: 7
148:       args: -ksp_gmres_cgs_refinement_type refine_always -pc_type asm -pc_asm_blocks 6 -f ${DATAFILESPATH}/matrices/small -matload_block_size 6 -ksp_monitor_short
149:       requires: datafilespath double !complex !defined(PETSC_USE_64BIT_INDICES)

151:     test:
152:       requires: double !complex !defined(PETSC_USE_64BIT_INDICES)
153:       suffix: 3
154:       filter: sed -e "s/CONVERGED_RTOL/CONVERGED_ATOL/g"
155:       args: -f ${wPETSC_DIR}/share/petsc/datafiles/matrices/spd-real-int32-float64 -pc_type none -ksp_type {{cg groppcg pipecg pipecgrr pipelcg pipeprcg cgne nash stcg gltr fcg pipefcg gmres pipefgmres fgmres lgmres dgmres pgmres tcqmr bcgs ibcgs qmrcgs fbcgs fbcgsr bcgsl pipebcgs cgs tfqmr cr pipecr lsqr qcg bicg minres symmlq lcd gcr pipegcr cgls}} -ksp_max_it 20 -ksp_error_if_not_converged -ksp_converged_reason -test_residual

157:     test:
158:       requires: double !complex !defined(PETSC_USE_64BIT_INDICES)
159:       suffix: 3_maxits
160:       output_file: output/ex6_maxits.out
161:       args: -f ${wPETSC_DIR}/share/petsc/datafiles/matrices/spd-real-int32-float64 -pc_type none -ksp_type {{chebyshev cg groppcg pipecg pipecgrr pipelcg pipeprcg cgne nash stcg gltr fcg pipefcg gmres pipefgmres fgmres lgmres dgmres pgmres tcqmr bcgs ibcgs qmrcgs fbcgs fbcgsr bcgsl pipebcgs cgs tfqmr cr pipecr qcg bicg minres symmlq lcd gcr pipegcr cgls richardson}} -ksp_max_it 4 -ksp_error_if_not_converged -ksp_converged_maxits -ksp_converged_reason -test_residual -ksp_norm_type none

163:     testset:
164:       requires: double !complex !defined(PETSC_USE_64BIT_INDICES)
165:       output_file: output/ex6_skip.out
166:       args: -f ${wPETSC_DIR}/share/petsc/datafiles/matrices/spd-real-int32-float64 -pc_type none -ksp_max_it 8 -ksp_error_if_not_converged -ksp_convergence_test skip -ksp_converged_reason -test_residual
167:       #SYMMLQ converges in 4 iterations and then generate nans
168:       test:
169:         suffix: 3_skip
170:         args: -ksp_type {{chebyshev cg groppcg pipecg pipecgrr pipelcg pipeprcg cgne nash stcg gltr fcg pipefcg gmres fgmres lgmres dgmres pgmres tcqmr bcgs ibcgs qmrcgs fbcgs fbcgsr bcgsl pipebcgs cgs tfqmr cr pipecr qcg bicg minres lcd gcr cgls richardson}}
171:       #PIPEGCR generates nans on linux-knl
172:       #PIPEFGMRES can have happy breakdown which is not handled well with no convergence test
173:       test:
174:         requires: !defined(PETSC_USE_AVX512_KERNELS)
175:         suffix: 3_skip_pipegcr
176:         args: -ksp_type pipegcr
177:       test:
178:         requires: hpddm
179:         suffix: 3_skip_hpddm
180:         args: -ksp_type hpddm -ksp_hpddm_type {{cg gmres bgmres bcg bfbcg gcrodr bgcrodr}}

182:     test:
183:       requires: double !complex !defined(PETSC_USE_64BIT_INDICES) hpddm
184:       suffix: 3_hpddm
185:       output_file: output/ex6_3.out
186:       filter: sed -e "s/CONVERGED_RTOL/CONVERGED_ATOL/g"
187:       args: -f ${wPETSC_DIR}/share/petsc/datafiles/matrices/spd-real-int32-float64 -pc_type none -ksp_type hpddm -ksp_hpddm_type {{cg gmres bgmres bcg bfbcg gcrodr bgcrodr}} -ksp_max_it 20 -ksp_error_if_not_converged -ksp_converged_reason -test_residual

189:     # test CG shortcut for residual access
190:     test:
191:       suffix: 4
192:       args: -ksp_converged_reason -ksp_max_it 20 -ksp_converged_maxits -ksp_type {{cg pipecg groppcg}} -ksp_norm_type {{preconditioned unpreconditioned natural}separate output} -pc_type {{bjacobi none}separate output} -f ${DATAFILESPATH}/matrices/poisson_2d13p -b_in_f 0 -test_residual
193:       requires: datafilespath double !complex !defined(PETSC_USE_64BIT_INDICES)

195: TEST*/