Actual source code: test2.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 SVD with different builds with a matrix loaded from a file"
23: " (matrices available in PETSc's distribution).\n\n";
25: #include <slepcsvd.h>
29: int main(int argc,char **argv)
30: {
31: Mat A; /* operator matrix */
32: SVD svd; /* singular value problem solver context */
33: char filename[PETSC_MAX_PATH_LEN];
34: const char *prefix,*scalar,*ints,*floats;
35: PetscReal tol=1000*PETSC_MACHINE_EPSILON;
36: PetscViewer viewer;
39: SlepcInitialize(&argc,&argv,(char*)0,help);
41: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
42: Load the matrix for which the SVD must be computed
43: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
44: #if defined(PETSC_USE_COMPLEX)
45: prefix = "nh";
46: scalar = "complex";
47: #else
48: prefix = "ns";
49: scalar = "real";
50: #endif
51: #if defined(PETSC_USE_64BIT_INDICES)
52: ints = "int64";
53: #else
54: ints = "int32";
55: #endif
56: #if defined(PETSC_USE_REAL_DOUBLE)
57: floats = "float64";
58: #elif defined(PETSC_USE_REAL_SINGLE)
59: floats = "float32";
60: #endif
62: PetscSNPrintf(filename,PETSC_MAX_PATH_LEN,"%s/share/petsc/datafiles/matrices/%s-%s-%s-%s",PETSC_DIR,prefix,scalar,ints,floats);
63: PetscPrintf(PETSC_COMM_WORLD,"\nReading matrix from binary file...\n\n");
64: PetscViewerBinaryOpen(PETSC_COMM_WORLD,filename,FILE_MODE_READ,&viewer);
65: MatCreate(PETSC_COMM_WORLD,&A);
66: MatSetFromOptions(A);
67: MatLoad(A,viewer);
68: PetscViewerDestroy(&viewer);
70: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
71: Create the SVD solver
72: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
73: SVDCreate(PETSC_COMM_WORLD,&svd);
74: SVDSetOperator(svd,A);
75: SVDSetTolerances(svd,tol,PETSC_DEFAULT);
76: SVDSetFromOptions(svd);
78: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
79: Solve the eigensystem and display solution
80: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
81: SVDSolve(svd);
82: SVDErrorView(svd,SVD_ERROR_RELATIVE,NULL);
83: SVDDestroy(&svd);
84: MatDestroy(&A);
85: SlepcFinalize();
86: return ierr;
87: }