Date: 2024-10-28T09:14:19+00:00

Actual source code: ex14.c
slepc-3.22.1 2024-10-28
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      1: /*
      2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
      4:    Copyright (c) 2002-, Universitat Politecnica de Valencia, Spain

      6:    This file is part of SLEPc.
      7:    SLEPc is distributed under a 2-clause BSD license (see LICENSE).
      8:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      9: */

     11: static char help[] = "Solves a singular value problem with the matrix loaded from a file.\n"
     12:   "This example works for both real and complex numbers.\n\n"
     13:   "The command line options are:\n"
     14:   "  -file <filename>, where <filename> = matrix file in PETSc binary form.\n\n";

     16: #include <slepcsvd.h>

     18: int main(int argc,char **argv)
     19: {
     20:   Mat            A;               /* operator matrix */
     21:   SVD            svd;             /* singular value problem solver context */
     22:   SVDType        type;
     23:   PetscReal      tol;
     24:   PetscInt       nsv,maxit,its;
     25:   char           filename[PETSC_MAX_PATH_LEN];
     26:   PetscViewer    viewer;
     27:   PetscBool      flg,terse;

     29:   PetscFunctionBeginUser;
     30:   PetscCall(SlepcInitialize(&argc,&argv,NULL,help));

     32:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     33:         Load the operator matrix that defines the singular value problem
     34:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

     36:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"\nSingular value problem stored in file.\n\n"));
     37:   PetscCall(PetscOptionsGetString(NULL,NULL,"-file",filename,sizeof(filename),&flg));
     38:   PetscCheck(flg,PETSC_COMM_WORLD,PETSC_ERR_USER_INPUT,"Must indicate a file name with the -file option");

     40: #if defined(PETSC_USE_COMPLEX)
     41:   PetscCall(PetscPrintf(PETSC_COMM_WORLD," Reading COMPLEX matrix from a binary file...\n"));
     42: #else
     43:   PetscCall(PetscPrintf(PETSC_COMM_WORLD," Reading REAL matrix from a binary file...\n"));
     44: #endif
     45:   PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD,filename,FILE_MODE_READ,&viewer));
     46:   PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
     47:   PetscCall(MatSetFromOptions(A));
     48:   PetscCall(MatLoad(A,viewer));
     49:   PetscCall(PetscViewerDestroy(&viewer));

     51:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     52:                 Create the singular value solver and set various options
     53:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

     55:   /*
     56:      Create singular value solver context
     57:   */
     58:   PetscCall(SVDCreate(PETSC_COMM_WORLD,&svd));

     60:   /*
     61:      Set operator
     62:   */
     63:   PetscCall(SVDSetOperators(svd,A,NULL));

     65:   /*
     66:      Set solver parameters at runtime
     67:   */
     68:   PetscCall(SVDSetFromOptions(svd));

     70:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     71:                       Solve the singular value system
     72:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

     74:   PetscCall(SVDSolve(svd));
     75:   PetscCall(SVDGetIterationNumber(svd,&its));
     76:   PetscCall(PetscPrintf(PETSC_COMM_WORLD," Number of iterations of the method: %" PetscInt_FMT "\n",its));

     78:   /*
     79:      Optional: Get some information from the solver and display it
     80:   */
     81:   PetscCall(SVDGetType(svd,&type));
     82:   PetscCall(PetscPrintf(PETSC_COMM_WORLD," Solution method: %s\n\n",type));
     83:   PetscCall(SVDGetDimensions(svd,&nsv,NULL,NULL));
     84:   PetscCall(PetscPrintf(PETSC_COMM_WORLD," Number of requested singular values: %" PetscInt_FMT "\n",nsv));
     85:   PetscCall(SVDGetTolerances(svd,&tol,&maxit));
     86:   PetscCall(PetscPrintf(PETSC_COMM_WORLD," Stopping condition: tol=%.4g, maxit=%" PetscInt_FMT "\n",(double)tol,maxit));

     88:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     89:                     Display solution and clean up
     90:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

     92:   /* show detailed info unless -terse option is given by user */
     93:   PetscCall(PetscOptionsHasName(NULL,NULL,"-terse",&terse));
     94:   if (terse) PetscCall(SVDErrorView(svd,SVD_ERROR_RELATIVE,NULL));
     95:   else {
     96:     PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL));
     97:     PetscCall(SVDConvergedReasonView(svd,PETSC_VIEWER_STDOUT_WORLD));
     98:     PetscCall(SVDErrorView(svd,SVD_ERROR_RELATIVE,PETSC_VIEWER_STDOUT_WORLD));
     99:     PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD));
    100:   }
    101:   PetscCall(SVDDestroy(&svd));
    102:   PetscCall(MatDestroy(&A));
    103:   PetscCall(SlepcFinalize());
    104:   return 0;
    105: }
    106: /*TEST

    108:    testset:
    109:       requires: double !complex !defined(PETSC_USE_64BIT_INDICES)
    110:       args: -file ${SLEPC_DIR}/share/slepc/datafiles/matrices/rdb200.petsc -terse
    111:       test:
    112:          suffix: 1
    113:          args: -svd_nsv 4 -svd_standard -svd_ncv 12 -svd_type {{trlanczos lanczos randomized cross}}
    114:          filter: grep -v method
    115:       test:
    116:          suffix: 1_scalapack
    117:          nsize: {{1 2 3}}
    118:          args: -svd_nsv 4 -svd_type scalapack
    119:          requires: scalapack
    120:       test:
    121:          suffix: 1_elemental
    122:          nsize: {{1 2 3}}
    123:          args: -svd_nsv 4 -svd_type elemental
    124:          output_file: output/ex14_1_scalapack.out
    125:          filter: sed -e "s/elemental/scalapack/"
    126:          requires: elemental
    127:       test:
    128:          suffix: 1_ksvd
    129:          nsize: 6
    130:          args: -svd_nsv 4 -svd_type ksvd -svd_ksvd_eigen_method {{mrrr elpa}} -svd_ksvd_polar_method {{qdwh zolopd}}
    131:          output_file: output/ex14_1_scalapack.out
    132:          filter: sed -e "s/ksvd/scalapack/"
    133:          requires: elpa polar ksvd
    134:       test:
    135:          suffix: 2
    136:          args: -svd_nsv 2 -svd_type cyclic -svd_cyclic_explicitmatrix -svd_cyclic_st_type sinvert -svd_cyclic_eps_target 12.5 -svd_cyclic_st_ksp_type preonly -svd_cyclic_st_pc_type lu -svd_view
    137:          filter: grep -v tolerance
    138:       test:
    139:          suffix: 2_cross
    140:          args: -svd_nsv 2 -svd_type cross -svd_cross_explicitmatrix -svd_cross_st_type sinvert -svd_cross_eps_target 100.0
    141:          filter: grep -v tolerance

    143:    testset:
    144:       requires: double complex datafilespath !defined(PETSC_USE_64BIT_INDICES)
    145:       args: -file ${DATAFILESPATH}/matrices/complex/qc324.petsc -terse
    146:       test:
    147:          suffix: 1_complex
    148:          args: -svd_nsv 4
    149:       test:
    150:          suffix: 1_complex_scalapack
    151:          nsize: {{1 2 3}}
    152:          args: -svd_nsv 4 -svd_type scalapack
    153:          requires: scalapack
    154:       test:
    155:          suffix: 1_complex_elemental
    156:          nsize: {{1 2 3}}
    157:          args: -svd_nsv 4 -svd_type elemental
    158:          requires: elemental
    159:       test:
    160:          suffix: 2_complex
    161:          args: -svd_nsv 2 -svd_type cyclic -svd_cyclic_explicitmatrix -svd_cyclic_st_type sinvert -svd_cyclic_eps_target 12.0 -svd_cyclic_st_ksp_type preonly -svd_cyclic_st_pc_type lu -svd_view
    162:          filter: grep -v tolerance

    164:    testset:
    165:       args: -svd_nsv 5 -svd_type randomized -svd_max_it 1 -svd_conv_maxit
    166:       test:
    167:          suffix: 3
    168:          args: -file ${SLEPC_DIR}/share/slepc/datafiles/matrices/rdb200.petsc
    169:          requires: double !complex !defined(PETSC_USE_64BIT_INDICES)
    170:       test:
    171:          suffix: 3_complex
    172:          args: -file ${DATAFILESPATH}/matrices/complex/qc324.petsc
    173:          requires: double complex datafilespath !defined(PETSC_USE_64BIT_INDICES)
    174:          filter: sed -e 's/[0-9][0-9]$//'

    176: TEST*/