Actual source code: test6.c
slepc-3.17.1 2022-04-11
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 DSGHIEP with compact storage.\n\n";
13: #include <slepcds.h>
15: int main(int argc,char **argv)
16: {
17: DS ds;
18: SlepcSC sc;
19: PetscReal *T,*s,re,im;
20: PetscScalar *eigr,*eigi;
21: PetscInt i,n=10,l=2,k=5,ld;
22: PetscViewer viewer;
23: PetscBool verbose;
25: SlepcInitialize(&argc,&argv,(char*)0,help);
26: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
27: PetscPrintf(PETSC_COMM_WORLD,"Solve a Dense System of type GHIEP with compact storage - dimension %" PetscInt_FMT ".\n",n);
28: PetscOptionsGetInt(NULL,NULL,"-l",&l,NULL);
29: PetscOptionsGetInt(NULL,NULL,"-k",&k,NULL);
31: PetscOptionsHasName(NULL,NULL,"-verbose",&verbose);
33: /* Create DS object */
34: DSCreate(PETSC_COMM_WORLD,&ds);
35: DSSetType(ds,DSGHIEP);
36: DSSetFromOptions(ds);
37: ld = n+2; /* test leading dimension larger than n */
38: DSAllocate(ds,ld);
39: DSSetDimensions(ds,n,l,k);
40: DSSetCompact(ds,PETSC_TRUE);
42: /* Set up viewer */
43: PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&viewer);
44: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO_DETAIL);
45: DSView(ds,viewer);
46: PetscViewerPopFormat(viewer);
47: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);
49: /* Fill arrow-tridiagonal matrix */
50: DSGetArrayReal(ds,DS_MAT_T,&T);
51: DSGetArrayReal(ds,DS_MAT_D,&s);
52: for (i=0;i<n;i++) T[i] = (PetscReal)(i+1);
53: for (i=k;i<n-1;i++) T[i+ld] = 1.0;
54: for (i=l;i<k;i++) T[i+2*ld] = 1.0;
55: T[2*ld+l+1] = -7; T[ld+k+1] = -7;
56: /* Signature matrix */
57: for (i=0;i<n;i++) s[i] = 1.0;
58: s[l+1] = -1.0;
59: s[k+1] = -1.0;
60: DSRestoreArrayReal(ds,DS_MAT_T,&T);
61: DSRestoreArrayReal(ds,DS_MAT_D,&s);
62: if (l==0 && k==0) DSSetState(ds,DS_STATE_INTERMEDIATE);
63: else DSSetState(ds,DS_STATE_RAW);
64: PetscPrintf(PETSC_COMM_WORLD,"Initial - - - - - - - - -\n");
65: DSView(ds,viewer);
67: /* Solve */
68: PetscCalloc2(n,&eigr,n,&eigi);
69: DSGetSlepcSC(ds,&sc);
70: sc->comparison = SlepcCompareLargestMagnitude;
71: sc->comparisonctx = NULL;
72: sc->map = NULL;
73: sc->mapobj = NULL;
74: DSSolve(ds,eigr,eigi);
75: DSSort(ds,eigr,eigi,NULL,NULL,NULL);
76: if (verbose) {
77: PetscPrintf(PETSC_COMM_WORLD,"After solve - - - - - - - - -\n");
78: DSView(ds,viewer);
79: }
81: /* Print eigenvalues */
82: PetscPrintf(PETSC_COMM_WORLD,"Computed eigenvalues =\n");
83: for (i=0;i<n;i++) {
84: #if defined(PETSC_USE_COMPLEX)
85: re = PetscRealPart(eigr[i]);
86: im = PetscImaginaryPart(eigr[i]);
87: #else
88: re = eigr[i];
89: im = eigi[i];
90: #endif
91: if (PetscAbs(im)<1e-10) PetscViewerASCIIPrintf(viewer," %.5f\n",(double)re);
92: else PetscViewerASCIIPrintf(viewer," %.5f%+.5fi\n",(double)re,(double)im);
93: }
94: PetscFree2(eigr,eigi);
95: DSDestroy(&ds);
96: SlepcFinalize();
97: return 0;
98: }
100: /*TEST
102: test:
103: suffix: 1
104: requires: !single
105: args: -ds_method {{0 1 2}}
106: filter: grep -v "solving the problem"
108: test:
109: suffix: 2
110: args: -n 5 -k 4 -l 4 -ds_method {{0 1 2}}
111: filter: grep -v "solving the problem"
113: TEST*/