Actual source code: ex50.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[] = "User-defined split preconditioner when solving a quadratic eigenproblem.\n\n"
12: "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 A[3],P[3]; /* problem matrices and split preconditioner matrices */
21: PEP pep; /* polynomial eigenproblem solver context */
22: ST st;
23: PetscInt N,n=10,m,Istart,Iend,II,i,j;
24: PetscBool flag,terse;
26: SlepcInitialize(&argc,&argv,(char*)0,help);
28: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
29: PetscOptionsGetInt(NULL,NULL,"-m",&m,&flag);
30: if (!flag) m=n;
31: N = n*m;
32: PetscPrintf(PETSC_COMM_WORLD,"\nQuadratic Eigenproblem, N=%" PetscInt_FMT " (%" PetscInt_FMT "x%" PetscInt_FMT " grid)\n\n",N,n,m);
34: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
35: Compute the matrices for (k^2*A_2+k*A_1+A_0)x=0, and their approximations
36: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
38: /* A[0] is the 2-D Laplacian */
39: MatCreate(PETSC_COMM_WORLD,&A[0]);
40: MatSetSizes(A[0],PETSC_DECIDE,PETSC_DECIDE,N,N);
41: MatSetFromOptions(A[0]);
42: MatSetUp(A[0]);
43: MatCreate(PETSC_COMM_WORLD,&P[0]);
44: MatSetSizes(P[0],PETSC_DECIDE,PETSC_DECIDE,N,N);
45: MatSetFromOptions(P[0]);
46: MatSetUp(P[0]);
48: MatGetOwnershipRange(A[0],&Istart,&Iend);
49: for (II=Istart;II<Iend;II++) {
50: i = II/n; j = II-i*n;
51: if (i>0) MatSetValue(A[0],II,II-n,-1.0,INSERT_VALUES);
52: if (i<m-1) MatSetValue(A[0],II,II+n,-1.0,INSERT_VALUES);
53: if (j>0) MatSetValue(A[0],II,II-1,-1.0,INSERT_VALUES);
54: if (j<n-1) MatSetValue(A[0],II,II+1,-1.0,INSERT_VALUES);
55: MatSetValue(A[0],II,II,4.0,INSERT_VALUES);
56: if (j>0) MatSetValue(P[0],II,II-1,-1.0,INSERT_VALUES);
57: if (j<n-1) MatSetValue(P[0],II,II+1,-1.0,INSERT_VALUES);
58: MatSetValue(P[0],II,II,4.0,INSERT_VALUES);
59: }
60: MatAssemblyBegin(A[0],MAT_FINAL_ASSEMBLY);
61: MatAssemblyEnd(A[0],MAT_FINAL_ASSEMBLY);
62: MatAssemblyBegin(P[0],MAT_FINAL_ASSEMBLY);
63: MatAssemblyEnd(P[0],MAT_FINAL_ASSEMBLY);
65: /* A[1] is the 1-D Laplacian on horizontal lines */
66: MatCreate(PETSC_COMM_WORLD,&A[1]);
67: MatSetSizes(A[1],PETSC_DECIDE,PETSC_DECIDE,N,N);
68: MatSetFromOptions(A[1]);
69: MatSetUp(A[1]);
70: MatCreate(PETSC_COMM_WORLD,&P[1]);
71: MatSetSizes(P[1],PETSC_DECIDE,PETSC_DECIDE,N,N);
72: MatSetFromOptions(P[1]);
73: MatSetUp(P[1]);
75: MatGetOwnershipRange(A[1],&Istart,&Iend);
76: for (II=Istart;II<Iend;II++) {
77: i = II/n; j = II-i*n;
78: if (j>0) MatSetValue(A[1],II,II-1,-1.0,INSERT_VALUES);
79: if (j<n-1) MatSetValue(A[1],II,II+1,-1.0,INSERT_VALUES);
80: MatSetValue(A[1],II,II,2.0,INSERT_VALUES);
81: MatSetValue(P[1],II,II,2.0,INSERT_VALUES);
82: }
83: MatAssemblyBegin(A[1],MAT_FINAL_ASSEMBLY);
84: MatAssemblyEnd(A[1],MAT_FINAL_ASSEMBLY);
85: MatAssemblyBegin(P[1],MAT_FINAL_ASSEMBLY);
86: MatAssemblyEnd(P[1],MAT_FINAL_ASSEMBLY);
88: /* A[2] is a diagonal matrix */
89: MatCreate(PETSC_COMM_WORLD,&A[2]);
90: MatSetSizes(A[2],PETSC_DECIDE,PETSC_DECIDE,N,N);
91: MatSetFromOptions(A[2]);
92: MatSetUp(A[2]);
93: MatCreate(PETSC_COMM_WORLD,&P[2]);
94: MatSetSizes(P[2],PETSC_DECIDE,PETSC_DECIDE,N,N);
95: MatSetFromOptions(P[2]);
96: MatSetUp(P[2]);
98: MatGetOwnershipRange(A[2],&Istart,&Iend);
99: for (II=Istart;II<Iend;II++) {
100: MatSetValue(A[2],II,II,(PetscReal)(II+1),INSERT_VALUES);
101: MatSetValue(P[2],II,II,(PetscReal)(II+1),INSERT_VALUES);
102: }
103: MatAssemblyBegin(A[2],MAT_FINAL_ASSEMBLY);
104: MatAssemblyEnd(A[2],MAT_FINAL_ASSEMBLY);
105: MatAssemblyBegin(P[2],MAT_FINAL_ASSEMBLY);
106: MatAssemblyEnd(P[2],MAT_FINAL_ASSEMBLY);
108: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
109: Create the eigensolver and set various options
110: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
112: PEPCreate(PETSC_COMM_WORLD,&pep);
113: PEPSetOperators(pep,3,A);
114: PEPSetProblemType(pep,PEP_HERMITIAN);
116: PEPGetST(pep,&st);
117: STSetType(st,STSINVERT);
118: STSetSplitPreconditioner(st,3,P,SUBSET_NONZERO_PATTERN);
120: PEPSetTarget(pep,-2.0);
121: PEPSetWhichEigenpairs(pep,PEP_TARGET_MAGNITUDE);
123: /*
124: Set solver parameters at runtime
125: */
126: PEPSetFromOptions(pep);
128: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
129: Solve the eigensystem, display solution and clean up
130: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
132: PEPSolve(pep);
133: /* show detailed info unless -terse option is given by user */
134: PetscOptionsHasName(NULL,NULL,"-terse",&terse);
135: if (terse) PEPErrorView(pep,PEP_ERROR_BACKWARD,NULL);
136: else {
137: PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL);
138: PEPConvergedReasonView(pep,PETSC_VIEWER_STDOUT_WORLD);
139: PEPErrorView(pep,PEP_ERROR_BACKWARD,PETSC_VIEWER_STDOUT_WORLD);
140: PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);
141: }
142: PEPDestroy(&pep);
143: MatDestroy(&A[0]);
144: MatDestroy(&A[1]);
145: MatDestroy(&A[2]);
146: MatDestroy(&P[0]);
147: MatDestroy(&P[1]);
148: MatDestroy(&P[2]);
149: SlepcFinalize();
150: return 0;
151: }
153: /*TEST
155: testset:
156: args: -pep_nev 4 -pep_ncv 28 -n 12 -terse
157: output_file: output/ex50_1.out
158: requires: double
159: test:
160: suffix: 1
161: args: -pep_type {{toar qarnoldi}}
162: test:
163: suffix: 1_linear
164: args: -pep_type linear -pep_general
166: testset:
167: args: -pep_all -n 12 -pep_type ciss -rg_type ellipse -rg_ellipse_center -1+1.5i -rg_ellipse_radius .3 -terse
168: output_file: output/ex50_2.out
169: requires: complex double
170: timeoutfactor: 2
171: test:
172: suffix: 2
173: test:
174: suffix: 2_par
175: nsize: 2
176: args: -pep_ciss_partitions 2
178: TEST*/