Actual source code: test17.c
slepc-3.18.1 2022-11-02
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 DSPEP with complex eigenvalues.\n\n";
13: #include <slepcds.h>
15: int main(int argc,char **argv)
16: {
17: DS ds;
18: SlepcSC sc;
19: Mat X;
20: Vec x0;
21: PetscScalar *K,*M,*wr,*wi;
22: PetscReal re,im,nrm;
23: PetscInt i,n=10,d=2,ld;
24: PetscViewer viewer;
25: PetscBool verbose;
28: SlepcInitialize(&argc,&argv,(char*)0,help);
29: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
30: PetscPrintf(PETSC_COMM_WORLD,"Solve a Dense System of type PEP - n=%" PetscInt_FMT ".\n",n);
31: PetscOptionsHasName(NULL,NULL,"-verbose",&verbose);
33: /* Create DS object */
34: DSCreate(PETSC_COMM_WORLD,&ds);
35: DSSetType(ds,DSPEP);
36: DSSetFromOptions(ds);
37: DSPEPSetDegree(ds,d);
39: /* Set dimensions */
40: ld = n+2; /* test leading dimension larger than n */
41: DSAllocate(ds,ld);
42: DSSetDimensions(ds,n,0,0);
44: /* Set up viewer */
45: PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&viewer);
46: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO_DETAIL);
47: DSView(ds,viewer);
48: PetscViewerPopFormat(viewer);
49: if (verbose) PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);
51: /* Fill matrices */
52: DSGetArray(ds,DS_MAT_E0,&K);
53: for (i=0;i<n;i++) K[i+i*ld] = 2.0;
54: for (i=1;i<n;i++) {
55: K[i+(i-1)*ld] = -1.0;
56: K[(i-1)+i*ld] = -1.0;
57: }
58: DSRestoreArray(ds,DS_MAT_E0,&K);
59: DSGetArray(ds,DS_MAT_E2,&M);
60: for (i=0;i<n;i++) M[i+i*ld] = 1.0;
61: DSRestoreArray(ds,DS_MAT_E2,&M);
63: if (verbose) {
64: PetscPrintf(PETSC_COMM_WORLD,"Initial - - - - - - - - -\n");
65: DSView(ds,viewer);
66: }
68: /* Solve */
69: PetscMalloc2(d*n,&wr,d*n,&wi);
70: DSGetSlepcSC(ds,&sc);
71: sc->comparison = SlepcCompareLargestImaginary;
72: sc->comparisonctx = NULL;
73: sc->map = NULL;
74: sc->mapobj = NULL;
75: DSSolve(ds,wr,wi);
76: DSSort(ds,wr,wi,NULL,NULL,NULL);
77: if (verbose) {
78: PetscPrintf(PETSC_COMM_WORLD,"After solve - - - - - - - - -\n");
79: DSView(ds,viewer);
80: }
82: /* Print eigenvalues */
83: PetscPrintf(PETSC_COMM_WORLD,"Computed eigenvalues =\n");
84: for (i=0;i<d*n;i++) {
85: #if defined(PETSC_USE_COMPLEX)
86: re = PetscRealPart(wr[i]);
87: im = PetscImaginaryPart(wr[i]);
88: #else
89: re = wr[i];
90: im = wi[i];
91: #endif
92: if (PetscAbs(im)<1e-10) PetscViewerASCIIPrintf(viewer," %.5f\n",(double)re);
93: else PetscViewerASCIIPrintf(viewer," %.5f%+.5fi\n",(double)re,(double)im);
94: }
96: /* Eigenvectors */
97: DSVectors(ds,DS_MAT_X,NULL,NULL); /* all eigenvectors */
98: DSGetMat(ds,DS_MAT_X,&X);
99: MatCreateVecs(X,NULL,&x0);
100: MatGetColumnVector(X,x0,1);
101: VecNorm(x0,NORM_2,&nrm);
102: DSRestoreMat(ds,DS_MAT_X,&X);
103: VecDestroy(&x0);
104: PetscPrintf(PETSC_COMM_WORLD,"Norm of 2nd column of X = %.3f\n",(double)nrm);
105: if (verbose) {
106: PetscPrintf(PETSC_COMM_WORLD,"After vectors - - - - - - - - -\n");
107: DSView(ds,viewer);
108: }
110: PetscFree2(wr,wi);
111: DSDestroy(&ds);
112: SlepcFinalize();
113: return 0;
114: }
116: /*TEST
118: test:
119: suffix: 1
120: args: -n 7
121: requires: !complex
122: filter: sed -e 's/-0.00000/0.00000/'
124: test:
125: suffix: 1_complex
126: args: -n 7
127: requires: complex
128: filter: sed -e 's/-0.00000/0.00000/'
130: TEST*/