Actual source code: test8.c
slepc-3.17.2 2022-08-09
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 functions of polynomial JD.\n\n"
12: "This is based on ex16.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 <slepcpep.h>
18: int main(int argc,char **argv)
19: {
20: Mat M,C,K,A[3]; /* problem matrices */
21: PEP pep; /* polynomial eigenproblem solver context */
22: PetscInt N,n=10,m,Istart,Iend,II,i,j,midx;
23: PetscReal restart,fix;
24: PetscBool flag,reuse;
25: PEPJDProjection proj;
27: SlepcInitialize(&argc,&argv,(char*)0,help);
29: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
30: PetscOptionsGetInt(NULL,NULL,"-m",&m,&flag);
31: if (!flag) m=n;
32: N = n*m;
33: PetscPrintf(PETSC_COMM_WORLD,"\nQuadratic Eigenproblem, N=%" PetscInt_FMT " (%" PetscInt_FMT "x%" PetscInt_FMT " grid)\n\n",N,n,m);
35: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
36: Compute the matrices that define the eigensystem, (k^2*M+k*C+K)x=0
37: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
39: /* K is the 2-D Laplacian */
40: MatCreate(PETSC_COMM_WORLD,&K);
41: MatSetSizes(K,PETSC_DECIDE,PETSC_DECIDE,N,N);
42: MatSetFromOptions(K);
43: MatSetUp(K);
44: MatGetOwnershipRange(K,&Istart,&Iend);
45: for (II=Istart;II<Iend;II++) {
46: i = II/n; j = II-i*n;
47: if (i>0) MatSetValue(K,II,II-n,-1.0,INSERT_VALUES);
48: if (i<m-1) MatSetValue(K,II,II+n,-1.0,INSERT_VALUES);
49: if (j>0) MatSetValue(K,II,II-1,-1.0,INSERT_VALUES);
50: if (j<n-1) MatSetValue(K,II,II+1,-1.0,INSERT_VALUES);
51: MatSetValue(K,II,II,4.0,INSERT_VALUES);
52: }
53: MatAssemblyBegin(K,MAT_FINAL_ASSEMBLY);
54: MatAssemblyEnd(K,MAT_FINAL_ASSEMBLY);
56: /* C is the 1-D Laplacian on horizontal lines */
57: MatCreate(PETSC_COMM_WORLD,&C);
58: MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,N,N);
59: MatSetFromOptions(C);
60: MatSetUp(C);
61: MatGetOwnershipRange(C,&Istart,&Iend);
62: for (II=Istart;II<Iend;II++) {
63: i = II/n; j = II-i*n;
64: if (j>0) MatSetValue(C,II,II-1,-1.0,INSERT_VALUES);
65: if (j<n-1) MatSetValue(C,II,II+1,-1.0,INSERT_VALUES);
66: MatSetValue(C,II,II,2.0,INSERT_VALUES);
67: }
68: MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);
69: MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);
71: /* M is a diagonal matrix */
72: MatCreate(PETSC_COMM_WORLD,&M);
73: MatSetSizes(M,PETSC_DECIDE,PETSC_DECIDE,N,N);
74: MatSetFromOptions(M);
75: MatSetUp(M);
76: MatGetOwnershipRange(M,&Istart,&Iend);
77: for (II=Istart;II<Iend;II++) MatSetValue(M,II,II,(PetscReal)(II+1),INSERT_VALUES);
78: MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY);
79: MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY);
81: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
82: Create the eigensolver and set various options
83: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
85: PEPCreate(PETSC_COMM_WORLD,&pep);
86: A[0] = K; A[1] = C; A[2] = M;
87: PEPSetOperators(pep,3,A);
88: PEPSetType(pep,PEPJD);
90: /*
91: Test interface functions of JD solver
92: */
93: PEPJDGetRestart(pep,&restart);
94: PetscPrintf(PETSC_COMM_WORLD," Restart parameter before changing = %g",(double)restart);
95: PEPJDSetRestart(pep,0.3);
96: PEPJDGetRestart(pep,&restart);
97: PetscPrintf(PETSC_COMM_WORLD," ... changed to %g\n",(double)restart);
99: PEPJDGetFix(pep,&fix);
100: PetscPrintf(PETSC_COMM_WORLD," Fix parameter before changing = %g",(double)fix);
101: PEPJDSetFix(pep,0.001);
102: PEPJDGetFix(pep,&fix);
103: PetscPrintf(PETSC_COMM_WORLD," ... changed to %g\n",(double)fix);
105: PEPJDGetReusePreconditioner(pep,&reuse);
106: PetscPrintf(PETSC_COMM_WORLD," Reuse preconditioner flag before changing = %d",(int)reuse);
107: PEPJDSetReusePreconditioner(pep,PETSC_TRUE);
108: PEPJDGetReusePreconditioner(pep,&reuse);
109: PetscPrintf(PETSC_COMM_WORLD," ... changed to %d\n",(int)reuse);
111: PEPJDGetProjection(pep,&proj);
112: PetscPrintf(PETSC_COMM_WORLD," Projection type before changing = %d",(int)proj);
113: PEPJDSetProjection(pep,PEP_JD_PROJECTION_ORTHOGONAL);
114: PEPJDGetProjection(pep,&proj);
115: PetscPrintf(PETSC_COMM_WORLD," ... changed to %d\n",(int)proj);
117: PEPJDGetMinimalityIndex(pep,&midx);
118: PetscPrintf(PETSC_COMM_WORLD," Minimality index before changing = %" PetscInt_FMT,midx);
119: PEPJDSetMinimalityIndex(pep,2);
120: PEPJDGetMinimalityIndex(pep,&midx);
121: PetscPrintf(PETSC_COMM_WORLD," ... changed to %" PetscInt_FMT "\n",midx);
123: PEPSetFromOptions(pep);
125: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
126: Solve the eigensystem
127: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
129: PEPSolve(pep);
130: PEPErrorView(pep,PEP_ERROR_BACKWARD,NULL);
131: PEPDestroy(&pep);
132: MatDestroy(&M);
133: MatDestroy(&C);
134: MatDestroy(&K);
135: SlepcFinalize();
136: return 0;
137: }
139: /*TEST
141: test:
142: args: -n 12 -pep_nev 2 -pep_ncv 21 -pep_conv_abs
144: TEST*/