Actual source code: test5.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 DSGHIEP.\n\n";
13: #include <slepcds.h>
15: int main(int argc,char **argv)
16: {
18: DS ds;
19: SlepcSC sc;
20: PetscReal re,im;
21: PetscScalar *A,*B,*eigr,*eigi;
22: PetscInt i,j,n=10,ld;
23: PetscViewer viewer;
24: PetscBool verbose;
26: SlepcInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
27: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
28: PetscPrintf(PETSC_COMM_WORLD,"Solve a Dense System of type GHIEP - dimension %D.\n",n);
29: PetscOptionsHasName(NULL,NULL,"-verbose",&verbose);
31: /* Create DS object */
32: DSCreate(PETSC_COMM_WORLD,&ds);
33: DSSetType(ds,DSGHIEP);
34: DSSetFromOptions(ds);
35: ld = n+2; /* test leading dimension larger than n */
36: DSAllocate(ds,ld);
37: DSSetDimensions(ds,n,0,0,0);
39: /* Set up viewer */
40: PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&viewer);
41: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO_DETAIL);
42: DSView(ds,viewer);
43: PetscViewerPopFormat(viewer);
44: if (verbose) {
45: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);
46: }
48: /* Fill with a symmetric Toeplitz matrix */
49: DSGetArray(ds,DS_MAT_A,&A);
50: DSGetArray(ds,DS_MAT_B,&B);
51: for (i=0;i<n;i++) A[i+i*ld]=2.0;
52: for (j=1;j<3;j++) {
53: for (i=0;i<n-j;i++) { A[i+(i+j)*ld]=1.0; A[(i+j)+i*ld]=1.0; }
54: }
55: for (j=1;j<3;j++) { A[0+j*ld]=-1.0*(j+2); A[j+0*ld]=-1.0*(j+2); }
56: /* Signature matrix */
57: for (i=0;i<n;i++) B[i+i*ld]=1.0;
58: B[0] = -1.0;
59: B[n-1+(n-1)*ld] = -1.0;
60: DSRestoreArray(ds,DS_MAT_A,&A);
61: DSRestoreArray(ds,DS_MAT_B,&B);
62: DSSetState(ds,DS_STATE_RAW);
63: if (verbose) {
64: PetscPrintf(PETSC_COMM_WORLD,"Initial - - - - - - - - -\n");
65: DSView(ds,viewer);
66: }
68: /* Solve */
69: PetscCalloc2(n,&eigr,n,&eigi);
70: DSGetSlepcSC(ds,&sc);
71: sc->comparison = SlepcCompareLargestMagnitude;
72: sc->comparisonctx = NULL;
73: sc->map = NULL;
74: sc->mapobj = NULL;
75: DSSolve(ds,eigr,eigi);
76: DSSort(ds,eigr,eigi,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<n;i++) {
85: #if defined(PETSC_USE_COMPLEX)
86: re = PetscRealPart(eigr[i]);
87: im = PetscImaginaryPart(eigr[i]);
88: #else
89: re = eigr[i];
90: im = eigi[i];
91: #endif
92: if (PetscAbs(im)<1e-10) {
93: PetscViewerASCIIPrintf(viewer," %.5f\n",(double)re);
94: } else {
95: PetscViewerASCIIPrintf(viewer," %.5f%+.5fi\n",(double)re,(double)im);
96: }
97: }
98: PetscFree2(eigr,eigi);
99: DSDestroy(&ds);
100: SlepcFinalize();
101: return ierr;
102: }
104: /*TEST
106: test:
107: suffix: 1
108: requires: !single
109: args: -ds_method {{0 1 2}}
110: filter: grep -v "solving the problem"
112: TEST*/