Actual source code: test5.c
slepc-3.6.1 2015-09-03
1: /*
2: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3: SLEPc - Scalable Library for Eigenvalue Problem Computations
4: Copyright (c) 2002-2015, 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 matrix rational function.\n\n";
24: #include <slepcfn.h>
28: int main(int argc,char **argv)
29: {
31: FN fn;
32: Mat A,B;
33: PetscInt i,j,n=10,np,nq;
34: PetscReal nrm;
35: PetscScalar *As,p[10],q[10];
36: PetscViewer viewer;
37: PetscBool verbose;
39: SlepcInitialize(&argc,&argv,(char*)0,help);
40: PetscOptionsGetInt(NULL,"-n",&n,NULL);
41: PetscOptionsHasName(NULL,"-verbose",&verbose);
42: PetscPrintf(PETSC_COMM_WORLD,"Matrix rational function, n=%D.\n",n);
44: /* Create rational function r(x)=p(x)/q(x) */
45: FNCreate(PETSC_COMM_WORLD,&fn);
46: FNSetType(fn,FNRATIONAL);
47: np = 2; nq = 3;
48: p[0] = -3.1; p[1] = 1.1;
49: q[0] = 1.0; q[1] = -2.0; q[2] = 3.5;
50: FNRationalSetNumerator(fn,np,p);
51: FNRationalSetDenominator(fn,nq,q);
52: FNSetFromOptions(fn);
54: /* Set up viewer */
55: PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&viewer);
56: FNView(fn,viewer);
57: if (verbose) {
58: PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);
59: }
61: /* Create matrices */
62: MatCreateSeqDense(PETSC_COMM_SELF,n,n,NULL,&A);
63: PetscObjectSetName((PetscObject)A,"A");
64: MatCreateSeqDense(PETSC_COMM_SELF,n,n,NULL,&B);
65: PetscObjectSetName((PetscObject)B,"B");
67: /* Fill A with a symmetric Toeplitz matrix */
68: MatDenseGetArray(A,&As);
69: for (i=0;i<n;i++) As[i+i*n]=2.0;
70: for (j=1;j<3;j++) {
71: for (i=0;i<n-j;i++) { As[i+(i+j)*n]=1.0; As[(i+j)+i*n]=1.0; }
72: }
73: MatDenseRestoreArray(A,&As);
74: MatSetOption(A,MAT_HERMITIAN,PETSC_TRUE);
75: if (verbose) {
76: PetscPrintf(PETSC_COMM_WORLD,"Matrix A - - - - - - - -\n");
77: MatView(A,viewer);
78: }
80: /* Evaluate matrix function */
81: FNEvaluateFunctionMat(fn,A,B);
82: if (verbose) {
83: PetscPrintf(PETSC_COMM_WORLD,"Computed f(A) - - - - - - -\n");
84: MatView(B,viewer);
85: }
86: MatNorm(B,NORM_1,&nrm);
87: PetscPrintf(PETSC_COMM_WORLD,"The 1-norm of f(A) is %g\n",(double)nrm);
89: /* Repeat with same matrix as non-symmetric */
90: MatSetOption(A,MAT_HERMITIAN,PETSC_FALSE);
92: /* Evaluate matrix function */
93: FNEvaluateFunctionMat(fn,A,B);
94: if (verbose) {
95: PetscPrintf(PETSC_COMM_WORLD,"Computed f(A) - - - - - - -\n");
96: MatView(B,viewer);
97: }
98: MatNorm(B,NORM_1,&nrm);
99: PetscPrintf(PETSC_COMM_WORLD,"The 1-norm of f(A) is %g\n",(double)nrm);
101: MatDestroy(&A);
102: MatDestroy(&B);
103: FNDestroy(&fn);
104: SlepcFinalize();
105: return 0;
106: }