Actual source code: test10.c

slepc-3.7.2 2016-07-19
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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 split reductions in BV.\n\n";

 24: #include <slepcbv.h>

 28: int main(int argc,char **argv)
 29: {
 31:   Vec            t,v,w,y,z,zsplit;
 32:   BV             X;
 33:   PetscInt       i,j,n=10,k=5;
 34:   PetscScalar    *zarray;
 35:   PetscReal      nrm;

 37:   SlepcInitialize(&argc,&argv,(char*)0,help);
 38:   PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
 39:   PetscOptionsGetInt(NULL,NULL,"-k",&k,NULL);
 40:   if (k<3) SETERRQ(PETSC_COMM_SELF,1,"Should specify at least k=3 columns");
 41:   PetscPrintf(PETSC_COMM_WORLD,"BV split ops (%D columns of dimension %D).\n",k,n);

 43:   /* Create template vector */
 44:   VecCreate(PETSC_COMM_WORLD,&t);
 45:   VecSetSizes(t,PETSC_DECIDE,n);
 46:   VecSetFromOptions(t);
 47:   VecDuplicate(t,&v);
 48:   VecSet(v,1.0);

 50:   /* Create BV object X */
 51:   BVCreate(PETSC_COMM_WORLD,&X);
 52:   PetscObjectSetName((PetscObject)X,"X");
 53:   BVSetSizesFromVec(X,t,k);
 54:   BVSetFromOptions(X);

 56:   /* Fill X entries */
 57:   for (j=0;j<k;j++) {
 58:     BVGetColumn(X,j,&w);
 59:     VecSet(w,0.0);
 60:     for (i=0;i<4;i++) {
 61:       if (i+j<n) {
 62:         VecSetValue(w,i+j,(PetscScalar)(3*i+j-2),INSERT_VALUES);
 63:       }
 64:     }
 65:     VecAssemblyBegin(w);
 66:     VecAssemblyEnd(w);
 67:     BVRestoreColumn(X,j,&w);
 68:   }

 70:   /* Use regular operations */
 71:   VecCreateSeq(PETSC_COMM_SELF,k+6,&z);
 72:   VecGetArray(z,&zarray);
 73:   BVGetColumn(X,0,&w);
 74:   VecDot(w,v,zarray);
 75:   BVRestoreColumn(X,0,&w);
 76:   BVDotVec(X,v,zarray+1);
 77:   BVDotColumn(X,2,zarray+1+k);

 79:   BVGetColumn(X,1,&y);
 80:   VecNorm(y,NORM_2,&nrm);
 81:   BVRestoreColumn(X,1,&y);
 82:   zarray[k+3] = nrm;
 83:   BVNormVec(X,v,NORM_2,&nrm);
 84:   zarray[k+4] = nrm;
 85:   BVNormColumn(X,0,NORM_2,&nrm);
 86:   zarray[k+5] = nrm;
 87:   VecRestoreArray(z,&zarray);

 89:   /* Use split operations */
 90:   VecCreateSeq(PETSC_COMM_SELF,k+6,&zsplit);
 91:   VecGetArray(zsplit,&zarray);
 92:   BVGetColumn(X,0,&w);
 93:   VecDotBegin(w,v,zarray);
 94:   BVDotVecBegin(X,v,zarray+1);
 95:   BVDotColumnBegin(X,2,zarray+1+k);
 96:   VecDotEnd(w,v,zarray);
 97:   BVRestoreColumn(X,0,&w);
 98:   BVDotVecEnd(X,v,zarray+1);
 99:   BVDotColumnEnd(X,2,zarray+1+k);

101:   BVGetColumn(X,1,&y);
102:   VecNormBegin(y,NORM_2,&nrm);
103:   BVNormVecBegin(X,v,NORM_2,&nrm);
104:   BVNormColumnBegin(X,0,NORM_2,&nrm);
105:   VecNormEnd(y,NORM_2,&nrm);
106:   BVRestoreColumn(X,1,&y);
107:   zarray[k+3] = nrm;
108:   BVNormVecEnd(X,v,NORM_2,&nrm);
109:   zarray[k+4] = nrm;
110:   BVNormColumnEnd(X,0,NORM_2,&nrm);
111:   zarray[k+5] = nrm;
112:   VecRestoreArray(zsplit,&zarray);

114:   /* Show difference */
115:   VecAXPY(z,-1.0,zsplit);
116:   VecNorm(z,NORM_1,&nrm);
117:   PetscSynchronizedPrintf(PETSC_COMM_WORLD,"%g\n",(double)nrm);
118:   PetscSynchronizedFlush(PETSC_COMM_WORLD,NULL);

120:   BVDestroy(&X);
121:   VecDestroy(&t);
122:   VecDestroy(&v);
123:   VecDestroy(&z);
124:   VecDestroy(&zsplit);
125:   SlepcFinalize();
126:   return ierr;
127: }