Date: 2022-08-02T03:14:48+00:00

Actual source code: ex79.c

      1: #include <petsc.h>

      3: static char help[] = "Solves a linear system with a block of right-hand sides, apply a preconditioner to the same block.\n\n";

      5: PetscErrorCode MatApply(PC pc, Mat X, Mat Y)
      6: {
      8:   MatCopy(X,Y,SAME_NONZERO_PATTERN);
      9:   return 0;
     10: }

     12: int main(int argc,char **args)
     13: {
     14:   Mat                X,B;         /* computed solutions and RHS */
     15:   Mat                A;           /* linear system matrix */
     16:   KSP                ksp;         /* linear solver context */
     17:   PC                 pc;          /* preconditioner context */
     18:   PetscInt           m = 10;
     19: #if defined(PETSC_USE_LOG)
     20:   PetscLogEvent      event;
     21: #endif
     22:   PetscEventPerfInfo info;

     24:   PetscInitialize(&argc,&args,NULL,help);
     25:   PetscLogDefaultBegin();
     26:   PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL);
     27:   MatCreateAIJ(PETSC_COMM_WORLD,m,m,PETSC_DECIDE,PETSC_DECIDE,m,NULL,m,NULL,&A);
     28:   MatCreateDense(PETSC_COMM_WORLD,m,PETSC_DECIDE,PETSC_DECIDE,m,NULL,&B);
     29:   MatCreateDense(PETSC_COMM_WORLD,m,PETSC_DECIDE,PETSC_DECIDE,m,NULL,&X);
     30:   MatSetRandom(A,NULL);
     31:   MatSetOption(A,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);
     32:   MatShift(A,10.0);
     33:   MatSetRandom(B,NULL);
     34:   KSPCreate(PETSC_COMM_WORLD,&ksp);
     35:   KSPSetOperators(ksp,A,A);
     36:   KSPSetFromOptions(ksp);
     37:   KSPGetPC(ksp,&pc);
     38:   PCShellSetMatApply(pc,MatApply);
     39:   KSPMatSolve(ksp,B,X);
     40:   PCMatApply(pc,B,X);
     41:   MatDestroy(&X);
     42:   MatDestroy(&B);
     43:   MatDestroy(&A);
     44:   KSPDestroy(&ksp);
     45:   PetscLogEventRegister("PCApply",PC_CLASSID,&event);
     46:   PetscLogEventGetPerfInfo(PETSC_DETERMINE,event,&info);
     48:   PetscLogEventRegister("PCMatApply",PC_CLASSID,&event);
     49:   PetscLogEventGetPerfInfo(PETSC_DETERMINE,event,&info);
     51:   PetscFinalize();
     52:   return 0;
     53: }

     55: /*TEST
     56:    # KSPHPDDM does either pseudo-blocking or "true" blocking, all tests should succeed with other -ksp_hpddm_type
     57:    testset:
     58:       nsize: 1
     59:       args: -pc_type {{bjacobi lu ilu mat cholesky icc none shell asm gasm}shared output}
     60:       test:
     61:          suffix: 1
     62:          output_file: output/ex77_preonly.out
     63:          args: -ksp_type preonly
     64:       test:
     65:          suffix: 1_hpddm
     66:          output_file: output/ex77_preonly.out
     67:          requires: hpddm
     68:          args: -ksp_type hpddm -ksp_hpddm_type preonly

     70:    testset:
     71:       nsize: 1
     72:       args: -pc_type ksp
     73:       test:
     74:          suffix: 2
     75:          output_file: output/ex77_preonly.out
     76:          args: -ksp_ksp_type preonly -ksp_type preonly
     77:       test:
     78:          suffix: 2_hpddm
     79:          output_file: output/ex77_preonly.out
     80:          requires: hpddm
     81:          args: -ksp_ksp_type hpddm -ksp_type hpddm -ksp_hpddm_type preonly -ksp_ksp_hpddm_type preonly

     83:    testset:
     84:       nsize: 1
     85:       requires: h2opus
     86:       args: -pc_type h2opus -pc_h2opus_init_mat_h2opus_leafsize 10
     87:       test:
     88:          suffix: 3
     89:          output_file: output/ex77_preonly.out
     90:          args: -ksp_type preonly
     91:       test:
     92:          suffix: 3_hpddm
     93:          output_file: output/ex77_preonly.out
     94:          requires: hpddm
     95:          args: -ksp_type hpddm -ksp_hpddm_type preonly

     97:    testset:
     98:       nsize: 1
     99:       requires: spai
    100:       args: -pc_type spai
    101:       test:
    102:          suffix: 4
    103:          output_file: output/ex77_preonly.out
    104:          args: -ksp_type preonly
    105:       test:
    106:          suffix: 4_hpddm
    107:          output_file: output/ex77_preonly.out
    108:          requires: hpddm
    109:          args: -ksp_type hpddm -ksp_hpddm_type preonly
    110:    # special code path in PCMatApply() for PCBJACOBI when a block is shared by multiple processes
    111:    testset:
    112:       nsize: 2
    113:       args: -pc_type bjacobi -pc_bjacobi_blocks 1 -sub_pc_type none
    114:       test:
    115:          suffix: 5
    116:          output_file: output/ex77_preonly.out
    117:          args: -ksp_type preonly -sub_ksp_type preonly
    118:       test:
    119:          suffix: 5_hpddm
    120:          output_file: output/ex77_preonly.out
    121:          requires: hpddm
    122:          args: -ksp_type hpddm -ksp_hpddm_type preonly -sub_ksp_type hpddm
    123:    # special code path in PCMatApply() for PCGASM when a block is shared by multiple processes
    124:    testset:
    125:       nsize: 2
    126:       args: -pc_type gasm -pc_gasm_total_subdomains 1 -sub_pc_type none
    127:       test:
    128:          suffix: 6
    129:          output_file: output/ex77_preonly.out
    130:          args: -ksp_type preonly -sub_ksp_type preonly
    131:       test:
    132:          suffix: 6_hpddm
    133:          output_file: output/ex77_preonly.out
    134:          requires: hpddm
    135:          args: -ksp_type hpddm -ksp_hpddm_type preonly -sub_ksp_type hpddm

    137:    testset:
    138:       nsize: 1
    139:       requires: suitesparse
    140:       args: -pc_type qr
    141:       test:
    142:          suffix: 7
    143:          output_file: output/ex77_preonly.out
    144:          args: -ksp_type preonly
    145:       test:
    146:          suffix: 7_hpddm
    147:          output_file: output/ex77_preonly.out
    148:          requires: hpddm
    149:          args: -ksp_type hpddm -ksp_hpddm_type preonly

    151: TEST*/