Actual source code: test1.c

slepc-3.7.1 2016-05-27
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  1: /*
  2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
  4:    Copyright (c) 2002-2016, 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 PEP without calling PEPSetFromOptions (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 <pep_type> = pep type to test.\n"
 27:   "  -epstype <eps_type> = eps type to test (for linear).\n\n";

 29: #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:   PEPType        type;
 38:   PetscInt       N,n=10,m,Istart,Iend,II,nev,maxit,i,j;
 39:   PetscBool      flag,isgd2,epsgiven;
 40:   char           peptype[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,NULL,"-n",&n,NULL);
 50:   PetscOptionsGetInt(NULL,NULL,"-m",&m,&flag);
 51:   if (!flag) m=n;
 52:   N = n*m;
 53:   PetscOptionsGetString(NULL,NULL,"-type",peptype,30,NULL);
 54:   PetscOptionsGetString(NULL,NULL,"-epstype",epstype,30,&epsgiven);
 55:   PetscPrintf(PETSC_COMM_WORLD,"\nQuadratic Eigenproblem, N=%D (%Dx%D grid)",N,n,m);
 56:   PetscPrintf(PETSC_COMM_WORLD,"\nPEP type: %s",peptype);
 57:   if (epsgiven) {
 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);
 71:   MatGetOwnershipRange(K,&Istart,&Iend);
 72:   for (II=Istart;II<Iend;II++) {
 73:     i = II/n; j = II-i*n;
 74:     if (i>0) { MatSetValue(K,II,II-n,-1.0,INSERT_VALUES); }
 75:     if (i<m-1) { MatSetValue(K,II,II+n,-1.0,INSERT_VALUES); }
 76:     if (j>0) { MatSetValue(K,II,II-1,-1.0,INSERT_VALUES); }
 77:     if (j<n-1) { MatSetValue(K,II,II+1,-1.0,INSERT_VALUES); }
 78:     MatSetValue(K,II,II,4.0,INSERT_VALUES);
 79:   }
 80:   MatAssemblyBegin(K,MAT_FINAL_ASSEMBLY);
 81:   MatAssemblyEnd(K,MAT_FINAL_ASSEMBLY);

 83:   /* C is the 1-D Laplacian on horizontal lines */
 84:   MatCreate(PETSC_COMM_WORLD,&C);
 85:   MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,N,N);
 86:   MatSetFromOptions(C);
 87:   MatSetUp(C);
 88:   MatGetOwnershipRange(C,&Istart,&Iend);
 89:   for (II=Istart;II<Iend;II++) {
 90:     i = II/n; j = II-i*n;
 91:     if (j>0) { MatSetValue(C,II,II-1,-1.0,INSERT_VALUES); }
 92:     if (j<n-1) { MatSetValue(C,II,II+1,-1.0,INSERT_VALUES); }
 93:     MatSetValue(C,II,II,2.0,INSERT_VALUES);
 94:   }
 95:   MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);
 96:   MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);

 98:   /* M is a diagonal matrix */
 99:   MatCreate(PETSC_COMM_WORLD,&M);
100:   MatSetSizes(M,PETSC_DECIDE,PETSC_DECIDE,N,N);
101:   MatSetFromOptions(M);
102:   MatSetUp(M);
103:   MatGetOwnershipRange(M,&Istart,&Iend);
104:   for (II=Istart;II<Iend;II++) {
105:     MatSetValue(M,II,II,(PetscReal)(II+1),INSERT_VALUES);
106:   }
107:   MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY);
108:   MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY);

110:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
111:                 Create the eigensolver and set various options
112:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

114:   PEPCreate(PETSC_COMM_WORLD,&pep);
115:   A[0] = K; A[1] = C; A[2] = M;
116:   PEPSetOperators(pep,3,A);
117:   PEPSetProblemType(pep,PEP_GENERAL);
118:   PEPSetDimensions(pep,4,20,PETSC_DEFAULT);
119:   PEPSetTolerances(pep,PETSC_SMALL,PETSC_DEFAULT);

121:   /*
122:      Set solver type at runtime
123:   */
124:   PEPSetType(pep,peptype);
125:   if (epsgiven) {
126:     PetscObjectTypeCompare((PetscObject)pep,PEPLINEAR,&flag);
127:     if (flag) {
128:       PEPLinearGetEPS(pep,&eps);
129:       PetscStrcmp(epstype,"gd2",&isgd2);
130:       if (isgd2) {
131:         EPSSetType(eps,EPSGD);
132:         EPSGDSetDoubleExpansion(eps,PETSC_TRUE);
133:       } else {
134:         EPSSetType(eps,epstype);
135:       }
136:       EPSGetST(eps,&st);
137:       STGetKSP(st,&ksp);
138:       KSPGetPC(ksp,&pc);
139:       PCSetType(pc,PCJACOBI);
140:       PetscObjectTypeCompare((PetscObject)eps,EPSGD,&flag);
141:     }
142:     PEPLinearSetExplicitMatrix(pep,PETSC_TRUE);
143:   }
144:   PetscObjectTypeCompare((PetscObject)pep,PEPQARNOLDI,&flag);
145:   if (flag) {
146:     PEPGetST(pep,&st);
147:     STSetTransform(st,PETSC_TRUE);
148:   }

150:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
151:                       Solve the eigensystem
152:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

154:   PEPSolve(pep);

156:   /*
157:      Optional: Get some information from the solver and display it
158:   */
159:   PEPGetType(pep,&type);
160:   PetscPrintf(PETSC_COMM_WORLD," Solution method: %s\n\n",type);
161:   PEPGetDimensions(pep,&nev,NULL,NULL);
162:   PetscPrintf(PETSC_COMM_WORLD," Number of requested eigenvalues: %D\n",nev);
163:   PEPGetTolerances(pep,NULL,&maxit);
164:   PetscPrintf(PETSC_COMM_WORLD," Stopping condition: maxit=%D\n",maxit);

166:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
167:                     Display solution and clean up
168:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

170:   PEPErrorView(pep,PEP_ERROR_BACKWARD,NULL);
171:   PEPDestroy(&pep);
172:   MatDestroy(&M);
173:   MatDestroy(&C);
174:   MatDestroy(&K);
175:   SlepcFinalize();
176:   return ierr;
177: }