Actual source code: test31.c

slepc-3.16.0 2021-09-30
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  1: /*
  2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
  4:    Copyright (c) 2002-2021, 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[] = "Test STFILTER interface functions.\n\n"
 12:   "Based on ex2.\n"
 13:   "The command line options are:\n"
 14:   "  -n <n>, where <n> = number of grid subdivisions in x dimension.\n"
 15:   "  -m <m>, where <m> = number of grid subdivisions in y dimension.\n\n";

 17: #include <slepceps.h>

 19: int main(int argc,char **argv)
 20: {
 21:   Mat            A;
 22:   EPS            eps;
 23:   ST             st;
 24:   PetscInt       N,n=10,m,Istart,Iend,II,i,j,degree;
 25:   PetscBool      flag,modify=PETSC_FALSE,terse;
 26:   PetscReal      inta,intb,rleft,rright;

 29:   SlepcInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
 30:   PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
 31:   PetscOptionsGetInt(NULL,NULL,"-m",&m,&flag);
 32:   if (!flag) m=n;
 33:   N = n*m;
 34:   PetscPrintf(PETSC_COMM_WORLD,"\n2-D Laplacian Eigenproblem, N=%D (%Dx%D grid)\n\n",N,n,m);
 35:   PetscOptionsGetBool(NULL,NULL,"-modify",&modify,&flag);

 37:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 38:                     Create the 2-D Laplacian
 39:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

 41:   MatCreate(PETSC_COMM_WORLD,&A);
 42:   MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,N,N);
 43:   MatSetFromOptions(A);
 44:   MatSetUp(A);
 45:   MatGetOwnershipRange(A,&Istart,&Iend);
 46:   for (II=Istart;II<Iend;II++) {
 47:     i = II/n; j = II-i*n;
 48:     if (i>0) { MatSetValue(A,II,II-n,-1.0,INSERT_VALUES); }
 49:     if (i<m-1) { MatSetValue(A,II,II+n,-1.0,INSERT_VALUES); }
 50:     if (j>0) { MatSetValue(A,II,II-1,-1.0,INSERT_VALUES); }
 51:     if (j<n-1) { MatSetValue(A,II,II+1,-1.0,INSERT_VALUES); }
 52:     MatSetValue(A,II,II,4.0,INSERT_VALUES);
 53:   }
 54:   MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
 55:   MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);

 57:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 58:                 Create the eigensolver and set various options
 59:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

 61:   EPSCreate(PETSC_COMM_WORLD,&eps);
 62:   EPSSetOperators(eps,A,NULL);
 63:   EPSSetProblemType(eps,EPS_HEP);
 64:   EPSSetType(eps,EPSKRYLOVSCHUR);
 65:   EPSSetWhichEigenpairs(eps,EPS_ALL);
 66:   EPSSetInterval(eps,0.5,1.3);
 67:   EPSGetST(eps,&st);
 68:   STSetType(st,STFILTER);
 69:   EPSSetFromOptions(eps);

 71:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 72:                 Solve the problem and display the solution
 73:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

 75:   EPSSolve(eps);

 77:   /* print filter information */
 78:   PetscObjectTypeCompare((PetscObject)st,STFILTER,&flag);
 79:   if (flag) {
 80:     STFilterGetDegree(st,&degree);
 81:     PetscPrintf(PETSC_COMM_WORLD," Filter degree: %D\n",degree);
 82:     STFilterGetInterval(st,&inta,&intb);
 83:     STFilterGetRange(st,&rleft,&rright);
 84:     PetscPrintf(PETSC_COMM_WORLD," Requested interval: [%g,%g],  range: [%g,%g]\n\n",(double)inta,(double)intb,(double)rleft,(double)rright);
 85:   }

 87:   PetscOptionsHasName(NULL,NULL,"-terse",&terse);
 88:   if (terse) {
 89:     EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL);
 90:   } else {
 91:     PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL);
 92:     EPSConvergedReasonView(eps,PETSC_VIEWER_STDOUT_WORLD);
 93:     EPSErrorView(eps,EPS_ERROR_RELATIVE,PETSC_VIEWER_STDOUT_WORLD);
 94:     PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);
 95:   }

 97:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 98:               Solve the problem again after changing the matrix
 99:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
100:   if (modify) {
101:     MatSetValue(A,0,0,0.3,INSERT_VALUES);
102:     MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
103:     MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
104:     EPSSetOperators(eps,A,NULL);
105:     EPSSolve(eps);
106:     PetscOptionsHasName(NULL,NULL,"-terse",&terse);
107:     if (terse) {
108:       EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL);
109:     } else {
110:       PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL);
111:       EPSConvergedReasonView(eps,PETSC_VIEWER_STDOUT_WORLD);
112:       EPSErrorView(eps,EPS_ERROR_RELATIVE,PETSC_VIEWER_STDOUT_WORLD);
113:       PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);
114:     }
115:   }

117:   EPSDestroy(&eps);
118:   MatDestroy(&A);
119:   SlepcFinalize();
120:   return ierr;
121: }

123: /*TEST

125:    test:
126:       suffix: 1
127:       args: -terse
128:       filter: sed -e "s/0.161982,7.83797/0.162007,7.83897/"
129:       requires: !single

131:    test:
132:       suffix: 2
133:       args: -modify -st_filter_range -0.5,8 -terse
134:       requires: !single

136:    test:
137:       suffix: 3
138:       args: -modify -terse
139:       filter: sed -e "s/0.161982,7.83797/0.162007,7.83897/"
140:       requires: !single

142: TEST*/