2: static char help[] = "Tests MatIncreaseOverlap() - the parallel case. This example\n\
  3: is similar to ex40.c; here the index sets used are random. Input arguments are:\n\
  4:   -f <input_file> : file to load.  For example see $PETSC_DIR/share/petsc/datafiles/matrices\n\
  5:   -nd <size>      : > 0  no of domains per processor \n\
  6:   -ov <overlap>   : >=0  amount of overlap between domains\n\n";

  8: #include <petscmat.h>

 12: int main(int argc,char **args)
 13: {
 14:   PetscInt       nd = 2,ov=1,i,j,m,n,*idx,lsize;
 16:   PetscMPIInt    rank;
 17:   PetscBool      flg;
 18:   Mat            A,B;
 19:   char           file[PETSC_MAX_PATH_LEN];
 20:   PetscViewer    fd;
 21:   IS             *is1,*is2;
 22:   PetscRandom    r;
 23:   PetscScalar    rand;

 25:   PetscInitialize(&argc,&args,(char*)0,help);
 26: #if defined(PETSC_USE_COMPLEX)
 27:   SETERRQ(PETSC_COMM_WORLD,1,"This example does not work with complex numbers");
 28: #else

 30:   MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
 31:   PetscOptionsGetString(NULL,"-f",file,PETSC_MAX_PATH_LEN,NULL);
 32:   PetscOptionsGetInt(NULL,"-nd",&nd,NULL);
 33:   PetscOptionsGetInt(NULL,"-ov",&ov,NULL);

 35:   /* Read matrix and RHS */
 36:   PetscViewerBinaryOpen(PETSC_COMM_WORLD,file,FILE_MODE_READ,&fd);
 37:   MatCreate(PETSC_COMM_WORLD,&A);
 38:   MatSetType(A,MATMPIAIJ);
 39:   MatLoad(A,fd);
 40:   PetscViewerDestroy(&fd);

 42:   /* Read the matrix again as a seq matrix */
 43:   PetscViewerBinaryOpen(PETSC_COMM_SELF,file,FILE_MODE_READ,&fd);
 44:   MatCreate(PETSC_COMM_SELF,&B);
 45:   MatSetType(B,MATSEQAIJ);
 46:   MatLoad(B,fd);
 47:   PetscViewerDestroy(&fd);

 49:   /* Create the Random no generator */
 50:   MatGetSize(A,&m,&n);
 51:   PetscRandomCreate(PETSC_COMM_SELF,&r);
 52:   PetscRandomSetFromOptions(r);

 54:   /* Create the IS corresponding to subdomains */
 55:   PetscMalloc1(nd,&is1);
 56:   PetscMalloc1(nd,&is2);
 57:   PetscMalloc1(m ,&idx);

 59:   /* Create the random Index Sets */
 60:   for (i=0; i<nd; i++) {
 61:     for (j=0; j<rank; j++) {
 62:       PetscRandomGetValue(r,&rand);
 63:     }
 64:     PetscRandomGetValue(r,&rand);
 65:     lsize = (PetscInt)(rand*m);
 66:     for (j=0; j<lsize; j++) {
 67:       PetscRandomGetValue(r,&rand);
 68:       idx[j] = (PetscInt)(rand*m);
 69:     }
 70:     ISCreateGeneral(PETSC_COMM_SELF,lsize,idx,PETSC_COPY_VALUES,is1+i);
 71:     ISCreateGeneral(PETSC_COMM_SELF,lsize,idx,PETSC_COPY_VALUES,is2+i);
 72:   }

 74:   MatIncreaseOverlap(A,nd,is1,ov);
 75:   MatIncreaseOverlap(B,nd,is2,ov);

 77:   /* Now see if the serial and parallel case have the same answers */
 78:   for (i=0; i<nd; ++i) {
 79:     PetscInt sz1,sz2;
 80:     ISEqual(is1[i],is2[i],&flg);
 81:     ISGetSize(is1[i],&sz1);
 82:     ISGetSize(is2[i],&sz2);
 83:     PetscPrintf(PETSC_COMM_SELF,"[%d], i=%D, flg =%d sz1 = %D sz2 = %D\n",rank,i,(int)flg,sz1,sz2);
 84:     /* ISView(is1[i],PETSC_VIEWER_STDOUT_SELF);
 85:     ISView(is2[i],PETSC_VIEWER_STDOUT_SELF); */
 86:   }

 88:   /* Free Allocated Memory */
 89:   for (i=0; i<nd; ++i) {
 90:     ISDestroy(&is1[i]);
 91:     ISDestroy(&is2[i]);
 92:   }
 93:   PetscRandomDestroy(&r);
 94:   PetscFree(is1);
 95:   PetscFree(is2);
 96:   MatDestroy(&A);
 97:   MatDestroy(&B);
 98:   PetscFree(idx);

100:   PetscFinalize();
101: #endif
102:   return 0;
103: }