Actual source code: test4.c
1: /*
2: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3: SLEPc - Scalable Library for Eigenvalue Problem Computations
4: Copyright (c) 2002-2012, Universitat Politecnica de Valencia, Spain
6: This file is part of SLEPc.
7:
8: SLEPc is free software: you can redistribute it and/or modify it under the
9: terms of version 3 of the GNU Lesser General Public License as published by
10: the Free Software Foundation.
12: SLEPc is distributed in the hope that it will be useful, but WITHOUT ANY
13: WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
14: FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
15: more details.
17: You should have received a copy of the GNU Lesser General Public License
18: along with SLEPc. If not, see <http://www.gnu.org/licenses/>.
19: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
20: */
22: static char help[] = "Test DSGNHEP.\n\n";
24: #include slepcds.h
28: int main( int argc, char **argv )
29: {
31: DS ds;
32: PetscScalar *A,*B,*wr,*wi;
33: PetscReal re,im;
34: PetscInt i,j,n=10,ld;
35: PetscViewer viewer;
36: PetscBool verbose;
38: SlepcInitialize(&argc,&argv,(char*)0,help);
39: PetscOptionsGetInt(PETSC_NULL,"-n",&n,PETSC_NULL);
40: PetscPrintf(PETSC_COMM_WORLD,"Solve a Dense System of type GNHEP - dimension %D.\n",n);
41: PetscOptionsHasName(PETSC_NULL,"-verbose",&verbose);
43: /* Create DS object */
44: DSCreate(PETSC_COMM_WORLD,&ds);
45: DSSetType(ds,DSGNHEP);
46: DSSetFromOptions(ds);
47: ld = n+2; /* test leading dimension larger than n */
48: DSAllocate(ds,ld);
49: DSSetDimensions(ds,n,PETSC_IGNORE,0,0);
51: /* Set up viewer */
52: PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&viewer);
53: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO_DETAIL);
54: DSView(ds,viewer);
55: PetscViewerPopFormat(viewer);
56: if (verbose) {
57: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);
58: }
60: /* Fill A with Grcar matrix */
61: DSGetArray(ds,DS_MAT_A,&A);
62: PetscMemzero(A,sizeof(PetscScalar)*ld*n);
63: for (i=1;i<n;i++) A[i+(i-1)*ld]=-1.0;
64: for (j=0;j<4;j++) {
65: for (i=0;i<n-j;i++) A[i+(i+j)*ld]=1.0;
66: }
67: DSRestoreArray(ds,DS_MAT_A,&A);
68: /* Fill B with an identity matrix */
69: DSGetArray(ds,DS_MAT_B,&B);
70: PetscMemzero(B,sizeof(PetscScalar)*ld*n);
71: for (i=0;i<n;i++) B[i+i*ld]=1.0;
72: DSRestoreArray(ds,DS_MAT_B,&B);
73:
74: if (verbose) {
75: PetscPrintf(PETSC_COMM_WORLD,"Initial - - - - - - - - -\n");
76: DSView(ds,viewer);
77: }
79: /* Solve */
80: PetscMalloc(n*sizeof(PetscScalar),&wr);
81: PetscMalloc(n*sizeof(PetscScalar),&wi);
82: DSSetEigenvalueComparison(ds,SlepcCompareLargestMagnitude,PETSC_NULL);
83: DSSolve(ds,wr,wi);
84: DSSort(ds,wr,wi,PETSC_NULL,PETSC_NULL,PETSC_NULL);
85: if (verbose) {
86: PetscPrintf(PETSC_COMM_WORLD,"After solve - - - - - - - - -\n");
87: DSView(ds,viewer);
88: }
90: /* Print eigenvalues */
91: PetscPrintf(PETSC_COMM_WORLD,"Computed eigenvalues =\n",n);
92: for (i=0;i<n;i++) {
93: #if defined(PETSC_USE_COMPLEX)
94: re = PetscRealPart(wr[i]);
95: im = PetscImaginaryPart(wr[i]);
96: #else
97: re = wr[i];
98: im = wi[i];
99: #endif
100: if (PetscAbs(im)<1e-10) { PetscViewerASCIIPrintf(viewer," %.5F\n",re); }
101: else { PetscViewerASCIIPrintf(viewer," %.5F%+.5Fi\n",re,im); }
102: }
104: PetscFree(wr);
105: PetscFree(wi);
106: DSDestroy(&ds);
107: SlepcFinalize();
108: return 0;
109: }