Actual source code: test1.c
1: /*
2: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3: SLEPc - Scalable Library for Eigenvalue Problem Computations
4: Copyright (c) 2002-2013, Universitat Politecnica de Valencia, Spain
6: This file is part of SLEPc.
8: SLEPc is free software: you can redistribute it and/or modify it under the
9: terms of version 3 of the GNU Lesser General Public License as published by
10: the Free Software Foundation.
12: SLEPc is distributed in the hope that it will be useful, but WITHOUT ANY
13: WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
14: FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
15: more details.
17: You should have received a copy of the GNU Lesser General Public License
18: along with SLEPc. If not, see <http://www.gnu.org/licenses/>.
19: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
20: */
22: static char help[] = "Test the solution of a QEP without calling QEPSetFromOptions (based on ex16.c).\n\n"
23: "The command line options are:\n"
24: " -n <n>, where <n> = number of grid subdivisions in x dimension.\n"
25: " -m <m>, where <m> = number of grid subdivisions in y dimension.\n"
26: " -type <qep_type> = qep type to test.\n"
27: " -epstype <eps_type> = eps type to test (for linear).\n\n";
29: #include <slepcqep.h>
33: int main(int argc,char **argv)
34: {
35: Mat M,C,K; /* problem matrices */
36: QEP qep; /* quadratic eigenproblem solver context */
37: QEPType type;
38: PetscInt N,n=10,m,Istart,Iend,II,nev,maxit,i,j;
39: PetscBool flag,isgd2;
40: char qeptype[30] = "linear",epstype[30] = "";
41: EPS eps;
42: ST st;
43: KSP ksp;
44: PC pc;
47: SlepcInitialize(&argc,&argv,(char*)0,help);
49: PetscOptionsGetInt(NULL,"-n",&n,NULL);
50: PetscOptionsGetInt(NULL,"-m",&m,&flag);
51: if (!flag) m=n;
52: N = n*m;
53: PetscOptionsGetString(NULL,"-type",qeptype,30,NULL);
54: PetscOptionsGetString(NULL,"-epstype",epstype,30,&flag);
55: PetscPrintf(PETSC_COMM_WORLD,"\nQuadratic Eigenproblem, N=%D (%Dx%D grid)",N,n,m);
56: PetscPrintf(PETSC_COMM_WORLD,"\nQEP type: %s",qeptype);
57: if (flag) {
58: PetscPrintf(PETSC_COMM_WORLD,"\nEPS type: %s",epstype);
59: }
60: PetscPrintf(PETSC_COMM_WORLD,"\n\n");
62: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
63: Compute the matrices that define the eigensystem, (k^2*M+k*C+K)x=0
64: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
66: /* K is the 2-D Laplacian */
67: MatCreate(PETSC_COMM_WORLD,&K);
68: MatSetSizes(K,PETSC_DECIDE,PETSC_DECIDE,N,N);
69: MatSetFromOptions(K);
70: MatSetUp(K);
72: MatGetOwnershipRange(K,&Istart,&Iend);
73: for (II=Istart;II<Iend;II++) {
74: i = II/n; j = II-i*n;
75: if (i>0) { MatSetValue(K,II,II-n,-1.0,INSERT_VALUES); }
76: if (i<m-1) { MatSetValue(K,II,II+n,-1.0,INSERT_VALUES); }
77: if (j>0) { MatSetValue(K,II,II-1,-1.0,INSERT_VALUES); }
78: if (j<n-1) { MatSetValue(K,II,II+1,-1.0,INSERT_VALUES); }
79: MatSetValue(K,II,II,4.0,INSERT_VALUES);
80: }
82: MatAssemblyBegin(K,MAT_FINAL_ASSEMBLY);
83: MatAssemblyEnd(K,MAT_FINAL_ASSEMBLY);
85: /* C is the zero matrix */
86: MatCreate(PETSC_COMM_WORLD,&C);
87: MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,N,N);
88: MatSetFromOptions(C);
89: MatSetUp(C);
90: MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);
91: MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);
93: /* M is the identity matrix */
94: MatCreate(PETSC_COMM_WORLD,&M);
95: MatSetSizes(M,PETSC_DECIDE,PETSC_DECIDE,N,N);
96: MatSetFromOptions(M);
97: MatSetUp(M);
98: MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY);
99: MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY);
100: MatShift(M,1.0);
102: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
103: Create the eigensolver and set various options
104: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
106: /*
107: Create eigensolver context
108: */
109: QEPCreate(PETSC_COMM_WORLD,&qep);
111: /*
112: Set matrices and problem type
113: */
114: QEPSetOperators(qep,M,C,K);
115: QEPSetProblemType(qep,QEP_GENERAL);
116: QEPSetDimensions(qep,4,20,PETSC_DEFAULT);
117: QEPSetTolerances(qep,PETSC_SMALL,PETSC_DEFAULT);
119: /*
120: Set solver type at runtime
121: */
122: QEPSetType(qep,qeptype);
123: if (flag) {
124: PetscObjectTypeCompare((PetscObject)qep,QEPLINEAR,&flag);
125: if (flag) {
126: QEPLinearGetEPS(qep,&eps);
127: PetscStrcmp(epstype,"gd2",&isgd2);
128: if (isgd2) {
129: EPSSetType(eps,EPSGD);
130: EPSGDSetDoubleExpansion(eps,PETSC_TRUE);
131: } else {
132: EPSSetType(eps,epstype);
133: }
134: EPSGetST(eps,&st);
135: STGetKSP(st,&ksp);
136: KSPGetPC(ksp,&pc);
137: PCSetType(pc,PCJACOBI);
138: PetscObjectTypeCompare((PetscObject)eps,EPSGD,&flag);
139: }
140: }
142: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
143: Solve the eigensystem
144: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
146: QEPSolve(qep);
148: /*
149: Optional: Get some information from the solver and display it
150: */
151: QEPGetType(qep,&type);
152: PetscPrintf(PETSC_COMM_WORLD," Solution method: %s\n\n",type);
153: QEPGetDimensions(qep,&nev,NULL,NULL);
154: PetscPrintf(PETSC_COMM_WORLD," Number of requested eigenvalues: %D\n",nev);
155: QEPGetTolerances(qep,NULL,&maxit);
156: PetscPrintf(PETSC_COMM_WORLD," Stopping condition: maxit=%D\n",maxit);
158: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
159: Display solution and clean up
160: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
162: QEPPrintSolution(qep,NULL);
164: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
165: Free work space
166: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
168: QEPDestroy(&qep);
169: MatDestroy(&M);
170: MatDestroy(&C);
171: MatDestroy(&K);
172: SlepcFinalize();
173: return 0;
174: }