Actual source code: test31.c
slepc-3.18.0 2022-10-01
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[] = "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);
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=%" PetscInt_FMT " (%" PetscInt_FMT "x%" PetscInt_FMT " 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,°ree);
81: PetscPrintf(PETSC_COMM_WORLD," Filter degree: %" PetscInt_FMT "\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) EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL);
89: else {
90: PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL);
91: EPSConvergedReasonView(eps,PETSC_VIEWER_STDOUT_WORLD);
92: EPSErrorView(eps,EPS_ERROR_RELATIVE,PETSC_VIEWER_STDOUT_WORLD);
93: PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);
94: }
96: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
97: Solve the problem again after changing the matrix
98: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
99: if (modify) {
100: MatSetValue(A,0,0,0.3,INSERT_VALUES);
101: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
102: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
103: EPSSetOperators(eps,A,NULL);
104: EPSSolve(eps);
105: PetscOptionsHasName(NULL,NULL,"-terse",&terse);
106: if (terse) EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL);
107: else {
108: PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL);
109: EPSConvergedReasonView(eps,PETSC_VIEWER_STDOUT_WORLD);
110: EPSErrorView(eps,EPS_ERROR_RELATIVE,PETSC_VIEWER_STDOUT_WORLD);
111: PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);
112: }
113: }
115: EPSDestroy(&eps);
116: MatDestroy(&A);
117: SlepcFinalize();
118: return 0;
119: }
121: /*TEST
123: test:
124: suffix: 1
125: args: -terse
126: filter: sed -e "s/0.161982,7.83797/0.162007,7.83897/"
127: requires: !single
129: test:
130: suffix: 2
131: args: -modify -st_filter_range -0.5,8 -terse
132: requires: !single
134: test:
135: suffix: 3
136: args: -modify -terse
137: filter: sed -e "s/0.161982,7.83797/0.162007,7.83897/"
138: requires: !single
140: TEST*/