Actual source code: test17.c
slepc-3.11.2 2019-07-30
1: /*
2: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3: SLEPc - Scalable Library for Eigenvalue Problem Computations
4: Copyright (c) 2002-2019, 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: {
18: DS ds;
19: SlepcSC sc;
20: Mat X;
21: Vec x0;
22: PetscScalar *K,*M,*wr,*wi;
23: PetscReal re,im,nrm;
24: PetscInt i,n=10,d=2,ld;
25: PetscViewer viewer;
26: PetscBool verbose;
28: SlepcInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
29: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
30: PetscPrintf(PETSC_COMM_WORLD,"Solve a Dense System of type PEP - n=%D.\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,0,0,0);
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) {
50: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);
51: }
53: /* Fill matrices */
54: DSGetArray(ds,DS_MAT_E0,&K);
55: for (i=0;i<n;i++) K[i+i*ld] = 2.0;
56: for (i=1;i<n;i++) {
57: K[i+(i-1)*ld] = -1.0;
58: K[(i-1)+i*ld] = -1.0;
59: }
60: DSRestoreArray(ds,DS_MAT_E0,&K);
61: DSGetArray(ds,DS_MAT_E2,&M);
62: for (i=0;i<n;i++) M[i+i*ld] = 1.0;
63: DSRestoreArray(ds,DS_MAT_E2,&M);
65: if (verbose) {
66: PetscPrintf(PETSC_COMM_WORLD,"Initial - - - - - - - - -\n");
67: DSView(ds,viewer);
68: }
70: /* Solve */
71: PetscMalloc2(d*n,&wr,d*n,&wi);
72: DSGetSlepcSC(ds,&sc);
73: sc->comparison = SlepcCompareLargestReal;
74: sc->comparisonctx = NULL;
75: sc->map = NULL;
76: sc->mapobj = NULL;
77: DSSolve(ds,wr,wi);
78: DSSort(ds,wr,wi,NULL,NULL,NULL);
79: if (verbose) {
80: PetscPrintf(PETSC_COMM_WORLD,"After solve - - - - - - - - -\n");
81: DSView(ds,viewer);
82: }
84: /* Print eigenvalues */
85: PetscPrintf(PETSC_COMM_WORLD,"Computed eigenvalues =\n");
86: for (i=0;i<d*n;i++) {
87: #if defined(PETSC_USE_COMPLEX)
88: re = PetscRealPart(wr[i]);
89: im = PetscImaginaryPart(wr[i]);
90: #else
91: re = wr[i];
92: im = wi[i];
93: #endif
94: if (PetscAbs(im)<1e-10) {
95: PetscViewerASCIIPrintf(viewer," %.5f\n",(double)re);
96: } else {
97: PetscViewerASCIIPrintf(viewer," %.5f%+.5fi\n",(double)re,(double)im);
98: }
99: }
101: /* Eigenvectors */
102: DSVectors(ds,DS_MAT_X,NULL,NULL); /* all eigenvectors */
103: DSGetMat(ds,DS_MAT_X,&X);
104: MatCreateVecs(X,NULL,&x0);
105: MatGetColumnVector(X,x0,1);
106: VecNorm(x0,NORM_2,&nrm);
107: MatDestroy(&X);
108: VecDestroy(&x0);
109: PetscPrintf(PETSC_COMM_WORLD,"Norm of 2nd column of X = %.3f\n",(double)nrm);
110: if (verbose) {
111: PetscPrintf(PETSC_COMM_WORLD,"After vectors - - - - - - - - -\n");
112: DSView(ds,viewer);
113: }
115: PetscFree2(wr,wi);
116: DSDestroy(&ds);
117: SlepcFinalize();
118: return ierr;
119: }
121: /*TEST
123: test:
124: suffix: 1
125: args: -n 7
126: requires: !complex
128: TEST*/