Line data    Source code

       1             : /*
       2             :    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
       3             :    SLEPc - Scalable Library for Eigenvalue Problem Computations
       4             :    Copyright (c) 2002-, Universitat Politecnica de Valencia, Spain
       5             : 
       6             :    This file is part of SLEPc.
       7             :    SLEPc is distributed under a 2-clause BSD license (see LICENSE).
       8             :    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
       9             : */
      10             : 
      11             : static char help[] = "Tests a user-defined convergence test.\n\n";
      12             : 
      13             : #include <slepceps.h>
      14             : 
      15             : /*
      16             :   MyConvergedAbsolute - Bizarre convergence test that requires more accuracy
      17             :   to positive eigenvalues compared to negative ones.
      18             : */
      19          62 : PetscErrorCode MyConvergedAbsolute(EPS eps,PetscScalar eigr,PetscScalar eigi,PetscReal res,PetscReal *errest,void *ctx)
      20             : {
      21          62 :   PetscFunctionBegin;
      22          62 :   *errest = (PetscRealPart(eigr)<0.0)?res:100*res;
      23          62 :   PetscFunctionReturn(PETSC_SUCCESS);
      24             : }
      25             : 
      26           1 : int main(int argc,char **argv)
      27             : {
      28           1 :   Mat            A;           /* problem matrix */
      29           1 :   EPS            eps;         /* eigenproblem solver context */
      30           1 :   PetscInt       n=30,i,Istart,Iend;
      31             : 
      32           1 :   PetscFunctionBeginUser;
      33           1 :   PetscCall(SlepcInitialize(&argc,&argv,NULL,help));
      34           1 :   PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
      35           1 :   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"\nTridiagonal Eigenproblem, n=%" PetscInt_FMT "\n\n",n));
      36             : 
      37             :   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      38             :      Compute the operator matrix that defines the eigensystem, Ax=kx
      39             :      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
      40             : 
      41           1 :   PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
      42           1 :   PetscCall(MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,n,n));
      43           1 :   PetscCall(MatSetFromOptions(A));
      44             : 
      45           1 :   PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
      46         201 :   for (i=Istart;i<Iend;i++) {
      47         200 :     if (i>0) PetscCall(MatSetValue(A,i,i-1,-1.0,INSERT_VALUES));
      48         200 :     if (i<n-1) PetscCall(MatSetValue(A,i,i+1,-1.0,INSERT_VALUES));
      49             :   }
      50           1 :   PetscCall(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY));
      51           1 :   PetscCall(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY));
      52           1 :   PetscCall(MatShift(A,-1e-3));
      53             : 
      54             :   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      55             :                         Create the eigensolver
      56             :      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
      57           1 :   PetscCall(EPSCreate(PETSC_COMM_WORLD,&eps));
      58           1 :   PetscCall(EPSSetOperators(eps,A,NULL));
      59           1 :   PetscCall(EPSSetProblemType(eps,EPS_HEP));
      60             :   /* set user-defined convergence test */
      61           1 :   PetscCall(EPSSetConvergenceTestFunction(eps,MyConvergedAbsolute,NULL,NULL));
      62           1 :   PetscCall(EPSSetFromOptions(eps));
      63             : 
      64             :   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      65             :                           Solve the problem
      66             :      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
      67           1 :   PetscCall(EPSSolve(eps));
      68           1 :   PetscCall(EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL));
      69             : 
      70           1 :   PetscCall(EPSDestroy(&eps));
      71           1 :   PetscCall(MatDestroy(&A));
      72           1 :   PetscCall(SlepcFinalize());
      73             :   return 0;
      74             : }
      75             : 
      76             : /*TEST
      77             : 
      78             :    test:
      79             :       suffix: 1
      80             :       args: -n 200 -eps_nev 6 -eps_ncv 24 -eps_smallest_magnitude
      81             :       requires: !single
      82             : 
      83             : TEST*/