Actual source code: test45.c
slepc-3.23.1 2025-05-01
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 interface to external package ChASE.\n\n"
12: "This is based on ex3.c. The command line options are:\n"
13: " -n <n>, where <n> = number of grid subdivisions in x dimension.\n"
14: " -m <m>, where <m> = number of grid subdivisions in y dimension.\n\n";
16: #include <slepceps.h>
18: int main(int argc,char **argv)
19: {
20: Mat A; /* matrix */
21: EPS eps; /* eigenproblem solver context */
22: PetscInt N,n=35,m,Istart,Iend,II,i,j,deg;
23: PetscBool opt,flag;
25: PetscFunctionBeginUser;
26: PetscCall(SlepcInitialize(&argc,&argv,NULL,help));
28: PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
29: PetscCall(PetscOptionsGetInt(NULL,NULL,"-m",&m,&flag));
30: if (!flag) m=n;
31: N = n*m;
32: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"\nStandard eigenproblem with ChASE, N=%" PetscInt_FMT " (%" PetscInt_FMT "x%" PetscInt_FMT " grid)\n\n",N,n,m));
34: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
35: Compute the matrix that defines the eigensystem, Ax=kx
36: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
38: PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
39: PetscCall(MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,N,N));
40: PetscCall(MatSetFromOptions(A));
42: PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
43: for (II=Istart;II<Iend;II++) {
44: i = II/n; j = II-i*n;
45: if (i>0) PetscCall(MatSetValue(A,II,II-n,-1.0,INSERT_VALUES));
46: if (i<m-1) PetscCall(MatSetValue(A,II,II+n,-1.0,INSERT_VALUES));
47: if (j>0) PetscCall(MatSetValue(A,II,II-1,-1.0,INSERT_VALUES));
48: if (j<n-1) PetscCall(MatSetValue(A,II,II+1,-1.0,INSERT_VALUES));
49: PetscCall(MatSetValue(A,II,II,4.0,INSERT_VALUES));
50: }
52: PetscCall(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY));
53: PetscCall(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY));
55: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
56: Create the eigensolver and set various options
57: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
59: PetscCall(EPSCreate(PETSC_COMM_WORLD,&eps));
60: PetscCall(EPSSetOperators(eps,A,NULL));
61: PetscCall(EPSSetProblemType(eps,EPS_HEP));
62: PetscCall(EPSSetType(eps,EPSCHASE));
63: PetscCall(EPSSetDimensions(eps,6,PETSC_DETERMINE,PETSC_DETERMINE));
64: PetscCall(EPSSetWhichEigenpairs(eps,EPS_SMALLEST_REAL));
65: deg = 20;
66: opt = PETSC_TRUE;
67: PetscCall(EPSCHASESetDegree(eps,deg,opt));
68: PetscCall(EPSSetFromOptions(eps));
70: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
71: Compute eigenvalues and display info
72: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
74: PetscCall(EPSSolve(eps));
75: PetscCall(EPSCHASEGetDegree(eps,°,&opt));
76: PetscCall(PetscPrintf(PETSC_COMM_WORLD," ChASE: using degree %" PetscInt_FMT ", optimization %s\n",deg,PetscBools[opt]));
78: PetscCall(EPSErrorView(eps,EPS_ERROR_ABSOLUTE,NULL));
80: PetscCall(EPSDestroy(&eps));
81: PetscCall(MatDestroy(&A));
82: PetscCall(SlepcFinalize());
83: return 0;
84: }
86: /*TEST
88: build:
89: requires: chase
91: testset:
92: requires: chase
93: output_file: output/test45_1.out
94: test:
95: suffix: 1
96: test:
97: suffix: 2
98: args: -mat_scalapack_grid_height 2
99: nsize: 2
101: TEST*/