Actual source code: ex50.c
slepc-3.18.2 2023-01-26
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;
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 for (k^2*A_2+k*A_1+A_0)x=0, and their approximations
37: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
39: /* A[0] is the 2-D Laplacian */
40: MatCreate(PETSC_COMM_WORLD,&A[0]);
41: MatSetSizes(A[0],PETSC_DECIDE,PETSC_DECIDE,N,N);
42: MatSetFromOptions(A[0]);
43: MatSetUp(A[0]);
44: MatCreate(PETSC_COMM_WORLD,&P[0]);
45: MatSetSizes(P[0],PETSC_DECIDE,PETSC_DECIDE,N,N);
46: MatSetFromOptions(P[0]);
47: MatSetUp(P[0]);
49: MatGetOwnershipRange(A[0],&Istart,&Iend);
50: for (II=Istart;II<Iend;II++) {
51: i = II/n; j = II-i*n;
52: if (i>0) MatSetValue(A[0],II,II-n,-1.0,INSERT_VALUES);
53: if (i<m-1) MatSetValue(A[0],II,II+n,-1.0,INSERT_VALUES);
54: if (j>0) MatSetValue(A[0],II,II-1,-1.0,INSERT_VALUES);
55: if (j<n-1) MatSetValue(A[0],II,II+1,-1.0,INSERT_VALUES);
56: MatSetValue(A[0],II,II,4.0,INSERT_VALUES);
57: if (j>0) MatSetValue(P[0],II,II-1,-1.0,INSERT_VALUES);
58: if (j<n-1) MatSetValue(P[0],II,II+1,-1.0,INSERT_VALUES);
59: MatSetValue(P[0],II,II,4.0,INSERT_VALUES);
60: }
61: MatAssemblyBegin(A[0],MAT_FINAL_ASSEMBLY);
62: MatAssemblyEnd(A[0],MAT_FINAL_ASSEMBLY);
63: MatAssemblyBegin(P[0],MAT_FINAL_ASSEMBLY);
64: MatAssemblyEnd(P[0],MAT_FINAL_ASSEMBLY);
66: /* A[1] is the 1-D Laplacian on horizontal lines */
67: MatCreate(PETSC_COMM_WORLD,&A[1]);
68: MatSetSizes(A[1],PETSC_DECIDE,PETSC_DECIDE,N,N);
69: MatSetFromOptions(A[1]);
70: MatSetUp(A[1]);
71: MatCreate(PETSC_COMM_WORLD,&P[1]);
72: MatSetSizes(P[1],PETSC_DECIDE,PETSC_DECIDE,N,N);
73: MatSetFromOptions(P[1]);
74: MatSetUp(P[1]);
76: MatGetOwnershipRange(A[1],&Istart,&Iend);
77: for (II=Istart;II<Iend;II++) {
78: i = II/n; j = II-i*n;
79: if (j>0) MatSetValue(A[1],II,II-1,-1.0,INSERT_VALUES);
80: if (j<n-1) MatSetValue(A[1],II,II+1,-1.0,INSERT_VALUES);
81: MatSetValue(A[1],II,II,2.0,INSERT_VALUES);
82: MatSetValue(P[1],II,II,2.0,INSERT_VALUES);
83: }
84: MatAssemblyBegin(A[1],MAT_FINAL_ASSEMBLY);
85: MatAssemblyEnd(A[1],MAT_FINAL_ASSEMBLY);
86: MatAssemblyBegin(P[1],MAT_FINAL_ASSEMBLY);
87: MatAssemblyEnd(P[1],MAT_FINAL_ASSEMBLY);
89: /* A[2] is a diagonal matrix */
90: MatCreate(PETSC_COMM_WORLD,&A[2]);
91: MatSetSizes(A[2],PETSC_DECIDE,PETSC_DECIDE,N,N);
92: MatSetFromOptions(A[2]);
93: MatSetUp(A[2]);
94: MatCreate(PETSC_COMM_WORLD,&P[2]);
95: MatSetSizes(P[2],PETSC_DECIDE,PETSC_DECIDE,N,N);
96: MatSetFromOptions(P[2]);
97: MatSetUp(P[2]);
99: MatGetOwnershipRange(A[2],&Istart,&Iend);
100: for (II=Istart;II<Iend;II++) {
101: MatSetValue(A[2],II,II,(PetscReal)(II+1),INSERT_VALUES);
102: MatSetValue(P[2],II,II,(PetscReal)(II+1),INSERT_VALUES);
103: }
104: MatAssemblyBegin(A[2],MAT_FINAL_ASSEMBLY);
105: MatAssemblyEnd(A[2],MAT_FINAL_ASSEMBLY);
106: MatAssemblyBegin(P[2],MAT_FINAL_ASSEMBLY);
107: MatAssemblyEnd(P[2],MAT_FINAL_ASSEMBLY);
109: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
110: Create the eigensolver and set various options
111: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
113: PEPCreate(PETSC_COMM_WORLD,&pep);
114: PEPSetOperators(pep,3,A);
115: PEPSetProblemType(pep,PEP_HERMITIAN);
117: PEPGetST(pep,&st);
118: STSetType(st,STSINVERT);
119: STSetSplitPreconditioner(st,3,P,SUBSET_NONZERO_PATTERN);
121: PEPSetTarget(pep,-2.0);
122: PEPSetWhichEigenpairs(pep,PEP_TARGET_MAGNITUDE);
124: /*
125: Set solver parameters at runtime
126: */
127: PEPSetFromOptions(pep);
129: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
130: Solve the eigensystem, display solution and clean up
131: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
133: PEPSolve(pep);
134: /* show detailed info unless -terse option is given by user */
135: PetscOptionsHasName(NULL,NULL,"-terse",&terse);
136: if (terse) PEPErrorView(pep,PEP_ERROR_BACKWARD,NULL);
137: else {
138: PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL);
139: PEPConvergedReasonView(pep,PETSC_VIEWER_STDOUT_WORLD);
140: PEPErrorView(pep,PEP_ERROR_BACKWARD,PETSC_VIEWER_STDOUT_WORLD);
141: PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);
142: }
143: PEPDestroy(&pep);
144: MatDestroy(&A[0]);
145: MatDestroy(&A[1]);
146: MatDestroy(&A[2]);
147: MatDestroy(&P[0]);
148: MatDestroy(&P[1]);
149: MatDestroy(&P[2]);
150: SlepcFinalize();
151: return 0;
152: }
154: /*TEST
156: testset:
157: args: -pep_nev 4 -pep_ncv 28 -n 12 -terse
158: output_file: output/ex50_1.out
159: requires: double
160: test:
161: suffix: 1
162: args: -pep_type {{toar qarnoldi}}
163: test:
164: suffix: 1_linear
165: args: -pep_type linear -pep_general
167: testset:
168: args: -pep_all -n 12 -pep_type ciss -rg_type ellipse -rg_ellipse_center -1+1.5i -rg_ellipse_radius .3 -terse
169: output_file: output/ex50_2.out
170: requires: complex double
171: timeoutfactor: 2
172: test:
173: suffix: 2
174: test:
175: suffix: 2_par
176: nsize: 2
177: args: -pep_ciss_partitions 2
179: TEST*/