Actual source code: test6.c
slepc-3.19.2 2023-09-05
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: */
10: /*
11: Example based on spring problem in NLEVP collection [1]. See the parameters
12: meaning at Example 2 in [2].
14: [1] T. Betcke, N. J. Higham, V. Mehrmann, C. Schroder, and F. Tisseur,
15: NLEVP: A Collection of Nonlinear Eigenvalue Problems, MIMS EPrint
16: 2010.98, November 2010.
17: [2] F. Tisseur, Backward error and condition of polynomial eigenvalue
18: problems, Linear Algebra and its Applications, 309 (2000), pp. 339--361,
19: April 2000.
20: */
22: static char help[] = "Tests multiple calls to PEPSolve with different matrix of different size.\n\n"
23: "This is based on the spring problem from NLEVP collection.\n\n"
24: "The command line options are:\n"
25: " -n <n> ... number of grid subdivisions.\n"
26: " -mu <value> ... mass (default 1).\n"
27: " -tau <value> ... damping constant of the dampers (default 10).\n"
28: " -kappa <value> ... damping constant of the springs (default 5).\n"
29: " -initv ... set an initial vector.\n\n";
31: #include <slepcpep.h>
33: int main(int argc,char **argv)
34: {
35: Mat M,C,K,A[3]; /* problem matrices */
36: PEP pep; /* polynomial eigenproblem solver context */
37: PetscInt n=30,Istart,Iend,i,nev;
38: PetscReal mu=1.0,tau=10.0,kappa=5.0;
39: PetscBool terse=PETSC_FALSE;
41: PetscFunctionBeginUser;
42: PetscCall(SlepcInitialize(&argc,&argv,(char*)0,help));
44: PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
45: PetscCall(PetscOptionsGetReal(NULL,NULL,"-mu",&mu,NULL));
46: PetscCall(PetscOptionsGetReal(NULL,NULL,"-tau",&tau,NULL));
47: PetscCall(PetscOptionsGetReal(NULL,NULL,"-kappa",&kappa,NULL));
49: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
50: Compute the matrices that define the eigensystem, (k^2*M+k*C+K)x=0
51: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
53: /* K is a tridiagonal */
54: PetscCall(MatCreate(PETSC_COMM_WORLD,&K));
55: PetscCall(MatSetSizes(K,PETSC_DECIDE,PETSC_DECIDE,n,n));
56: PetscCall(MatSetFromOptions(K));
57: PetscCall(MatSetUp(K));
59: PetscCall(MatGetOwnershipRange(K,&Istart,&Iend));
60: for (i=Istart;i<Iend;i++) {
61: if (i>0) PetscCall(MatSetValue(K,i,i-1,-kappa,INSERT_VALUES));
62: PetscCall(MatSetValue(K,i,i,kappa*3.0,INSERT_VALUES));
63: if (i<n-1) PetscCall(MatSetValue(K,i,i+1,-kappa,INSERT_VALUES));
64: }
66: PetscCall(MatAssemblyBegin(K,MAT_FINAL_ASSEMBLY));
67: PetscCall(MatAssemblyEnd(K,MAT_FINAL_ASSEMBLY));
69: /* C is a tridiagonal */
70: PetscCall(MatCreate(PETSC_COMM_WORLD,&C));
71: PetscCall(MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,n,n));
72: PetscCall(MatSetFromOptions(C));
73: PetscCall(MatSetUp(C));
75: PetscCall(MatGetOwnershipRange(C,&Istart,&Iend));
76: for (i=Istart;i<Iend;i++) {
77: if (i>0) PetscCall(MatSetValue(C,i,i-1,-tau,INSERT_VALUES));
78: PetscCall(MatSetValue(C,i,i,tau*3.0,INSERT_VALUES));
79: if (i<n-1) PetscCall(MatSetValue(C,i,i+1,-tau,INSERT_VALUES));
80: }
82: PetscCall(MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY));
83: PetscCall(MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY));
85: /* M is a diagonal matrix */
86: PetscCall(MatCreate(PETSC_COMM_WORLD,&M));
87: PetscCall(MatSetSizes(M,PETSC_DECIDE,PETSC_DECIDE,n,n));
88: PetscCall(MatSetFromOptions(M));
89: PetscCall(MatSetUp(M));
90: PetscCall(MatGetOwnershipRange(M,&Istart,&Iend));
91: for (i=Istart;i<Iend;i++) PetscCall(MatSetValue(M,i,i,mu,INSERT_VALUES));
92: PetscCall(MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY));
93: PetscCall(MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY));
95: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
96: Create the eigensolver and set various options
97: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
99: PetscCall(PEPCreate(PETSC_COMM_WORLD,&pep));
100: A[0] = K; A[1] = C; A[2] = M;
101: PetscCall(PEPSetOperators(pep,3,A));
102: PetscCall(PEPSetProblemType(pep,PEP_GENERAL));
103: PetscCall(PEPSetTolerances(pep,PETSC_SMALL,PETSC_DEFAULT));
104: PetscCall(PEPSetFromOptions(pep));
106: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
107: Solve the eigensystem
108: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
110: PetscCall(PEPSolve(pep));
111: PetscCall(PEPGetDimensions(pep,&nev,NULL,NULL));
112: PetscCall(PetscPrintf(PETSC_COMM_WORLD," Number of requested eigenvalues: %" PetscInt_FMT "\n",nev));
114: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
115: Display solution of first solve
116: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
117: PetscCall(PetscOptionsHasName(NULL,NULL,"-terse",&terse));
118: if (terse) PetscCall(PEPErrorView(pep,PEP_ERROR_BACKWARD,NULL));
119: else {
120: PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL));
121: PetscCall(PEPConvergedReasonView(pep,PETSC_VIEWER_STDOUT_WORLD));
122: PetscCall(PEPErrorView(pep,PEP_ERROR_RELATIVE,PETSC_VIEWER_STDOUT_WORLD));
123: PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD));
124: }
125: PetscCall(MatDestroy(&M));
126: PetscCall(MatDestroy(&C));
127: PetscCall(MatDestroy(&K));
129: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
130: Compute the eigensystem, (k^2*M+k*C+K)x=0 for bigger n
131: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
133: n *= 2;
134: /* K is a tridiagonal */
135: PetscCall(MatCreate(PETSC_COMM_WORLD,&K));
136: PetscCall(MatSetSizes(K,PETSC_DECIDE,PETSC_DECIDE,n,n));
137: PetscCall(MatSetFromOptions(K));
138: PetscCall(MatSetUp(K));
140: PetscCall(MatGetOwnershipRange(K,&Istart,&Iend));
141: for (i=Istart;i<Iend;i++) {
142: if (i>0) PetscCall(MatSetValue(K,i,i-1,-kappa,INSERT_VALUES));
143: PetscCall(MatSetValue(K,i,i,kappa*3.0,INSERT_VALUES));
144: if (i<n-1) PetscCall(MatSetValue(K,i,i+1,-kappa,INSERT_VALUES));
145: }
147: PetscCall(MatAssemblyBegin(K,MAT_FINAL_ASSEMBLY));
148: PetscCall(MatAssemblyEnd(K,MAT_FINAL_ASSEMBLY));
150: /* C is a tridiagonal */
151: PetscCall(MatCreate(PETSC_COMM_WORLD,&C));
152: PetscCall(MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,n,n));
153: PetscCall(MatSetFromOptions(C));
154: PetscCall(MatSetUp(C));
156: PetscCall(MatGetOwnershipRange(C,&Istart,&Iend));
157: for (i=Istart;i<Iend;i++) {
158: if (i>0) PetscCall(MatSetValue(C,i,i-1,-tau,INSERT_VALUES));
159: PetscCall(MatSetValue(C,i,i,tau*3.0,INSERT_VALUES));
160: if (i<n-1) PetscCall(MatSetValue(C,i,i+1,-tau,INSERT_VALUES));
161: }
163: PetscCall(MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY));
164: PetscCall(MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY));
166: /* M is a diagonal matrix */
167: PetscCall(MatCreate(PETSC_COMM_WORLD,&M));
168: PetscCall(MatSetSizes(M,PETSC_DECIDE,PETSC_DECIDE,n,n));
169: PetscCall(MatSetFromOptions(M));
170: PetscCall(MatSetUp(M));
171: PetscCall(MatGetOwnershipRange(M,&Istart,&Iend));
172: for (i=Istart;i<Iend;i++) PetscCall(MatSetValue(M,i,i,mu,INSERT_VALUES));
173: PetscCall(MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY));
174: PetscCall(MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY));
176: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
177: Solve again, calling PEPReset() since matrix size has changed
178: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
179: /* PetscCall(PEPReset(pep)); */ /* not required, will be called in PEPSetOperators() */
180: A[0] = K; A[1] = C; A[2] = M;
181: PetscCall(PEPSetOperators(pep,3,A));
182: PetscCall(PEPSolve(pep));
184: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
185: Display solution and clean up
186: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
187: if (terse) PetscCall(PEPErrorView(pep,PEP_ERROR_BACKWARD,NULL));
188: else {
189: PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL));
190: PetscCall(PEPConvergedReasonView(pep,PETSC_VIEWER_STDOUT_WORLD));
191: PetscCall(PEPErrorView(pep,PEP_ERROR_RELATIVE,PETSC_VIEWER_STDOUT_WORLD));
192: PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD));
193: }
194: PetscCall(PEPDestroy(&pep));
195: PetscCall(MatDestroy(&M));
196: PetscCall(MatDestroy(&C));
197: PetscCall(MatDestroy(&K));
198: PetscCall(SlepcFinalize());
199: return 0;
200: }
202: /*TEST
204: test:
205: suffix: 1
206: args: -pep_type {{toar qarnoldi linear}} -pep_nev 4 -terse
207: requires: double
209: test:
210: suffix: 2
211: args: -pep_type stoar -pep_hermitian -pep_nev 4 -terse
212: requires: !single
214: TEST*/