Actual source code: test3.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 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;
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 HEP 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);
32: PetscOptionsHasName(NULL,NULL,"-extrarow",&extrarow);
34: /* Create DS object */
35: DSCreate(PETSC_COMM_WORLD,&ds);
36: DSSetType(ds,DSHEP);
37: DSSetFromOptions(ds);
38: ld = n+2; /* test leading dimension larger than n */
39: DSAllocate(ds,ld);
40: DSSetDimensions(ds,n,l,k);
41: DSSetCompact(ds,PETSC_TRUE);
42: DSSetExtraRow(ds,extrarow);
44: /* Set up viewer */
45: PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&viewer);
46: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO_DETAIL);
47: DSView(ds,viewer);
48: PetscViewerPopFormat(viewer);
49: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);
51: /* Fill arrow-tridiagonal matrix */
52: DSGetArrayReal(ds,DS_MAT_T,&T);
53: for (i=0;i<n;i++) T[i] = (PetscReal)(i+1);
54: for (i=l;i<n-1;i++) T[i+ld] = 1.0;
55: if (extrarow) T[n-1+ld] = 1.0;
56: DSRestoreArrayReal(ds,DS_MAT_T,&T);
57: if (l==0 && k==0) DSSetState(ds,DS_STATE_INTERMEDIATE);
58: else DSSetState(ds,DS_STATE_RAW);
59: PetscPrintf(PETSC_COMM_WORLD,"Initial - - - - - - - - -\n");
60: DSView(ds,viewer);
62: /* Solve */
63: PetscMalloc1(n,&eig);
64: DSGetSlepcSC(ds,&sc);
65: sc->comparison = SlepcCompareLargestMagnitude;
66: sc->comparisonctx = NULL;
67: sc->map = NULL;
68: sc->mapobj = NULL;
69: DSSolve(ds,eig,NULL);
70: DSSort(ds,eig,NULL,NULL,NULL,NULL);
71: if (extrarow) DSUpdateExtraRow(ds);
72: if (verbose) {
73: PetscPrintf(PETSC_COMM_WORLD,"After solve - - - - - - - - -\n");
74: DSView(ds,viewer);
75: }
77: /* Print eigenvalues */
78: PetscPrintf(PETSC_COMM_WORLD,"Computed eigenvalues =\n");
79: for (i=0;i<n;i++) PetscViewerASCIIPrintf(viewer," %.5f\n",(double)PetscRealPart(eig[i]));
81: if (extrarow) {
82: /* Check that extra row is correct */
83: DSGetArrayReal(ds,DS_MAT_T,&T);
84: DSGetArray(ds,DS_MAT_Q,&Q);
85: d = 0.0;
86: for (i=l;i<n;i++) d += T[i+ld]-Q[n-1+i*ld];
87: 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));
88: DSRestoreArrayReal(ds,DS_MAT_T,&T);
89: DSRestoreArray(ds,DS_MAT_Q,&Q);
90: }
91: PetscFree(eig);
92: DSDestroy(&ds);
93: SlepcFinalize();
94: return 0;
95: }
97: /*TEST
99: testset:
100: args: -n 9 -ds_method {{0 1 2}}
101: filter: grep -v "solving the problem" | sed -e "s/extrarow//"
102: requires: !single
103: test:
104: suffix: 1
105: test:
106: suffix: 2
107: args: -extrarow
109: TEST*/