Actual source code: test3.c
slepc-3.18.3 2023-03-24
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 DSHEP 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;
20: PetscScalar *Q,*eig,d;
21: PetscInt i,n=10,l=2,k=5,ld;
22: PetscViewer viewer;
23: PetscBool verbose,extrarow;
26: SlepcInitialize(&argc,&argv,(char*)0,help);
27: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
28: PetscPrintf(PETSC_COMM_WORLD,"Solve a Dense System of type HEP with compact storage - dimension %" PetscInt_FMT ".\n",n);
29: PetscOptionsGetInt(NULL,NULL,"-l",&l,NULL);
30: PetscOptionsGetInt(NULL,NULL,"-k",&k,NULL);
32: PetscOptionsHasName(NULL,NULL,"-verbose",&verbose);
33: PetscOptionsHasName(NULL,NULL,"-extrarow",&extrarow);
35: /* Create DS object */
36: DSCreate(PETSC_COMM_WORLD,&ds);
37: DSSetType(ds,DSHEP);
38: DSSetFromOptions(ds);
39: ld = n+2; /* test leading dimension larger than n */
40: DSAllocate(ds,ld);
41: DSSetDimensions(ds,n,l,k);
42: DSSetCompact(ds,PETSC_TRUE);
43: DSSetExtraRow(ds,extrarow);
45: /* Set up viewer */
46: PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&viewer);
47: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO_DETAIL);
48: DSView(ds,viewer);
49: PetscViewerPopFormat(viewer);
50: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);
52: /* Fill arrow-tridiagonal matrix */
53: DSGetArrayReal(ds,DS_MAT_T,&T);
54: for (i=0;i<n;i++) T[i] = (PetscReal)(i+1);
55: for (i=l;i<n-1;i++) T[i+ld] = 1.0;
56: if (extrarow) T[n-1+ld] = 1.0;
57: DSRestoreArrayReal(ds,DS_MAT_T,&T);
58: if (l==0 && k==0) DSSetState(ds,DS_STATE_INTERMEDIATE);
59: else DSSetState(ds,DS_STATE_RAW);
60: PetscPrintf(PETSC_COMM_WORLD,"Initial - - - - - - - - -\n");
61: DSView(ds,viewer);
63: /* Solve */
64: PetscMalloc1(n,&eig);
65: DSGetSlepcSC(ds,&sc);
66: sc->comparison = SlepcCompareLargestMagnitude;
67: sc->comparisonctx = NULL;
68: sc->map = NULL;
69: sc->mapobj = NULL;
70: DSSolve(ds,eig,NULL);
71: DSSort(ds,eig,NULL,NULL,NULL,NULL);
72: if (extrarow) DSUpdateExtraRow(ds);
73: if (verbose) {
74: PetscPrintf(PETSC_COMM_WORLD,"After solve - - - - - - - - -\n");
75: DSView(ds,viewer);
76: }
78: /* Print eigenvalues */
79: PetscPrintf(PETSC_COMM_WORLD,"Computed eigenvalues =\n");
80: for (i=0;i<n;i++) PetscViewerASCIIPrintf(viewer," %.5f\n",(double)PetscRealPart(eig[i]));
82: if (extrarow) {
83: /* Check that extra row is correct */
84: DSGetArrayReal(ds,DS_MAT_T,&T);
85: DSGetArray(ds,DS_MAT_Q,&Q);
86: d = 0.0;
87: for (i=l;i<n;i++) d += T[i+ld]-Q[n-1+i*ld];
88: if (PetscAbsScalar(d)>10*PETSC_MACHINE_EPSILON) PetscPrintf(PETSC_COMM_WORLD,"Warning: there is a mismatch in the extra row of %g\n",(double)PetscAbsScalar(d));
89: DSRestoreArrayReal(ds,DS_MAT_T,&T);
90: DSRestoreArray(ds,DS_MAT_Q,&Q);
91: }
92: PetscFree(eig);
93: DSDestroy(&ds);
94: SlepcFinalize();
95: return 0;
96: }
98: /*TEST
100: testset:
101: args: -n 9 -ds_method {{0 1 2}}
102: filter: grep -v "solving the problem" | sed -e "s/extrarow//"
103: requires: !single
104: test:
105: suffix: 1
106: test:
107: suffix: 2
108: args: -extrarow
110: TEST*/