Actual source code: test3.c
slepc-3.7.2 2016-07-19
1: /*
2: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3: SLEPc - Scalable Library for Eigenvalue Problem Computations
4: Copyright (c) 2002-2016, Universitat Politecnica de Valencia, Spain
6: This file is part of SLEPc.
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 DSHEP with compact storage.\n\n";
24: #include <slepcds.h>
28: int main(int argc,char **argv)
29: {
31: DS ds;
32: SlepcSC sc;
33: PetscReal *T;
34: PetscScalar *eig;
35: PetscInt i,n=10,l=2,k=5,ld;
36: PetscViewer viewer;
37: PetscBool verbose,extrarow;
39: SlepcInitialize(&argc,&argv,(char*)0,help);
40: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
41: PetscPrintf(PETSC_COMM_WORLD,"Solve a Dense System of type HEP with compact storage - dimension %D.\n",n);
42: PetscOptionsGetInt(NULL,NULL,"-l",&l,NULL);
43: PetscOptionsGetInt(NULL,NULL,"-k",&k,NULL);
44: if (l>n || k>n || l>k) SETERRQ(PETSC_COMM_WORLD,1,"Wrong value of dimensions");
45: PetscOptionsHasName(NULL,NULL,"-verbose",&verbose);
46: PetscOptionsHasName(NULL,NULL,"-extrarow",&extrarow);
48: /* Create DS object */
49: DSCreate(PETSC_COMM_WORLD,&ds);
50: DSSetType(ds,DSHEP);
51: DSSetFromOptions(ds);
52: ld = n+2; /* test leading dimension larger than n */
53: DSAllocate(ds,ld);
54: DSSetDimensions(ds,n,0,l,k);
55: DSSetCompact(ds,PETSC_TRUE);
56: DSSetExtraRow(ds,extrarow);
58: /* Set up viewer */
59: PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&viewer);
60: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO_DETAIL);
61: DSView(ds,viewer);
62: PetscViewerPopFormat(viewer);
63: if (verbose) {
64: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);
65: }
67: /* Fill arrow-tridiagonal matrix */
68: DSGetArrayReal(ds,DS_MAT_T,&T);
69: for (i=0;i<n;i++) T[i] = (PetscReal)(i+1);
70: for (i=l;i<n-1;i++) T[i+ld] = 1.0;
71: if (extrarow) T[n-1+ld] = 1.0;
72: DSRestoreArrayReal(ds,DS_MAT_T,&T);
73: if (l==0 && k==0) {
74: DSSetState(ds,DS_STATE_INTERMEDIATE);
75: } else {
76: DSSetState(ds,DS_STATE_RAW);
77: }
78: if (verbose) {
79: PetscPrintf(PETSC_COMM_WORLD,"Initial - - - - - - - - -\n");
80: DSView(ds,viewer);
81: }
83: /* Solve */
84: PetscMalloc1(n,&eig);
85: DSGetSlepcSC(ds,&sc);
86: sc->comparison = SlepcCompareLargestMagnitude;
87: sc->comparisonctx = NULL;
88: sc->map = NULL;
89: sc->mapobj = NULL;
90: DSSolve(ds,eig,NULL);
91: DSSort(ds,eig,NULL,NULL,NULL,NULL);
92: if (extrarow) { DSUpdateExtraRow(ds); }
93: if (verbose) {
94: PetscPrintf(PETSC_COMM_WORLD,"After solve - - - - - - - - -\n");
95: DSView(ds,viewer);
96: }
98: /* Print eigenvalues */
99: PetscPrintf(PETSC_COMM_WORLD,"Computed eigenvalues =\n");
100: for (i=0;i<n;i++) {
101: PetscViewerASCIIPrintf(viewer," %.5f\n",(double)PetscRealPart(eig[i]));
102: }
104: PetscFree(eig);
105: DSDestroy(&ds);
106: SlepcFinalize();
107: return ierr;
108: }