Actual source code: test42.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[] = "Block-diagonal orthogonal eigenproblem.\n"
12: "The command line options are:\n"
13: " -n <n>, where <n> = matrix dimension.\n"
14: " -seed <s>, where <s> = seed for random number generation.\n\n";
16: #include <slepceps.h>
18: int main(int argc,char **argv)
19: {
20: EPS eps;
21: Mat A;
22: PetscRandom rand;
23: PetscScalar val,c,s;
24: PetscInt n=30,i,seed=0x12345678;
25: PetscMPIInt rank;
27: SlepcInitialize(&argc,&argv,(char*)0,help);
28: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
29: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
30: PetscPrintf(PETSC_COMM_WORLD,"\nOrthogonal eigenproblem, n=%" PetscInt_FMT "\n\n",n);
32: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
33: Generate the matrix
34: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
36: PetscRandomCreate(PETSC_COMM_WORLD,&rand);
37: PetscRandomSetFromOptions(rand);
38: PetscOptionsGetInt(NULL,NULL,"-seed",&seed,NULL);
39: PetscRandomSetSeed(rand,seed);
40: PetscRandomSeed(rand);
41: PetscRandomSetInterval(rand,0,2*PETSC_PI);
43: MatCreate(PETSC_COMM_WORLD,&A);
44: MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,n,n);
45: MatSetFromOptions(A);
46: MatSetUp(A);
48: if (!rank) {
49: for (i=0;i<n/2;i++) {
50: PetscRandomGetValue(rand,&val);
51: c = PetscCosReal(PetscRealPart(val));
52: s = PetscSinReal(PetscRealPart(val));
53: MatSetValue(A,2*i,2*i,c,INSERT_VALUES);
54: MatSetValue(A,2*i+1,2*i+1,c,INSERT_VALUES);
55: MatSetValue(A,2*i,2*i+1,s,INSERT_VALUES);
56: MatSetValue(A,2*i+1,2*i,-s,INSERT_VALUES);
57: }
58: if (n%2) MatSetValue(A,n-1,n-1,-1.0,INSERT_VALUES);
59: }
60: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
61: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
63: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
64: Create the eigensolver and solve the problem
65: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
67: EPSCreate(PETSC_COMM_WORLD,&eps);
68: EPSSetOperators(eps,A,NULL);
69: EPSSetProblemType(eps,EPS_NHEP);
70: EPSSetWhichEigenpairs(eps,EPS_LARGEST_REAL);
71: EPSSetFromOptions(eps);
72: EPSSolve(eps);
74: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
75: Display solution and clean up
76: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
78: EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL);
79: EPSDestroy(&eps);
80: MatDestroy(&A);
81: PetscRandomDestroy(&rand);
82: SlepcFinalize();
83: return 0;
84: }
86: /*TEST
88: testset:
89: requires: complex double
90: args: -eps_type ciss -eps_all -rg_type ring -rg_ring_center 0 -rg_ring_radius 1 -rg_ring_width 0.05 -rg_ring_startangle .93 -rg_ring_endangle .07
91: filter: sed -e "s/[+-]\([0-9]\.[0-9]*i\)/+-\\1/g"
92: test:
93: suffix: 1_ring
94: args: -eps_ciss_extraction {{ritz hankel}}
96: TEST*/