Date: 2026-01-20T11:35:37+00:00

Actual source code: test19.c

      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[] = "Tests the usage of object prefix.\n\n"
     12:   "The command line options are:\n"
     13:   "  -n <n>, where <n> = matrix dimension.\n\n";

     15: #include <slepceps.h>

     17: int main(int argc,char **argv)
     18: {
     19:   Mat            A;           /* problem matrix */
     20:   EPS            eps;         /* eigenproblem solver context */
     21:   PetscInt       n=30,i,Istart,Iend;
     22:   const char     *prefix;

     24:   PetscFunctionBeginUser;
     25:   PetscCall(SlepcInitialize(&argc,&argv,NULL,help));

     27:   PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
     28:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"\nDiagonal Eigenproblem, n=%" PetscInt_FMT "\n\n",n));

     30:   PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
     31:   PetscCall(MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,n,n));
     32:   PetscCall(MatSetFromOptions(A));
     33:   PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
     34:   for (i=Istart;i<Iend;i++) PetscCall(MatSetValue(A,i,i,i+1,INSERT_VALUES));
     35:   PetscCall(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY));
     36:   PetscCall(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY));

     38:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     39:            Create the eigensolver and mess up with the prefix
     40:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
     41:   PetscCall(EPSCreate(PETSC_COMM_WORLD,&eps));
     42:   PetscCall(EPSSetOptionsPrefix(eps,"check_"));
     43:   PetscCall(EPSAppendOptionsPrefix(eps,"myprefix_"));
     44:   PetscCall(EPSGetOptionsPrefix(eps,&prefix));
     45:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"EPS prefix is currently: %s\n\n",prefix));

     47:   PetscCall(EPSSetOperators(eps,A,NULL));
     48:   PetscCall(EPSSetProblemType(eps,EPS_HEP));
     49:   PetscCall(EPSSetFromOptions(eps));
     50:   PetscCall(EPSSolve(eps));

     52:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     53:                     Display solution and clean up
     54:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
     55:   PetscCall(EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL));
     56:   PetscCall(EPSDestroy(&eps));
     57:   PetscCall(MatDestroy(&A));
     58:   PetscCall(SlepcFinalize());
     59:   return 0;
     60: }

     62: /*TEST

     64:    test:
     65:       suffix: 1
     66:       args: -check_myprefix_eps_nev 2 -check_myprefix_st_type sinvert

     68: TEST*/