Actual source code: ex37.c

  1: /*$Id: ex37.c,v 1.22 2001/08/07 03:03:07 balay Exp $*/

  3: static char help[] = "Tests MatCopy() and MatStore/RetrieveValues().\n\n";

 5:  #include petscmat.h

  9: int main(int argc,char **args)
 10: {
 11:   Mat         C,A;
 12:   int         i, n = 10,midx[3],ierr;
 13:   PetscScalar v[3];
 14:   PetscTruth  flg;

 16:   PetscInitialize(&argc,&args,(char *)0,help);
 17:   PetscOptionsGetInt(PETSC_NULL,"-n",&n,PETSC_NULL);

 19:   MatCreate(PETSC_COMM_WORLD,PETSC_DECIDE,PETSC_DECIDE,n,n,&C);
 20:   MatSetFromOptions(C);
 21:   MatCreate(PETSC_COMM_WORLD,PETSC_DECIDE,PETSC_DECIDE,n,n,&A);
 22:   MatSetFromOptions(A);

 24:   v[0] = -1.; v[1] = 2.; v[2] = -1.;
 25:   for (i=1; i<n-1; i++){
 26:     midx[2] = i-1; midx[1] = i; midx[0] = i+1;
 27:     MatSetValues(C,1,&i,3,midx,v,INSERT_VALUES);
 28:   }
 29:   i = 0; midx[0] = 0; midx[1] = 1;
 30:   v[0] = 2.0; v[1] = -1.;
 31:   MatSetValues(C,1,&i,2,midx,v,INSERT_VALUES);
 32:   i = n-1; midx[0] = n-2; midx[1] = n-1;
 33:   v[0] = -1.0; v[1] = 2.;
 34:   MatSetValues(C,1,&i,2,midx,v,INSERT_VALUES);

 36:   MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);
 37:   MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);

 39:   /* test matrices with different nonzero patterns */
 40:   MatCopy(C,A,DIFFERENT_NONZERO_PATTERN);

 42:   /* Now C and A have the same nonzero pattern */
 43:   MatSetOption(C,MAT_NO_NEW_NONZERO_LOCATIONS);
 44:   MatSetOption(A,MAT_NO_NEW_NONZERO_LOCATIONS);
 45:   MatCopy(C,A,SAME_NONZERO_PATTERN);

 47:   MatView(C,PETSC_VIEWER_STDOUT_WORLD);
 48:   MatView(A,PETSC_VIEWER_STDOUT_WORLD);

 50:   MatEqual(A,C,&flg);
 51:   if (flg) {
 52:     PetscPrintf(PETSC_COMM_WORLD,"Matrices are equal\n");
 53:   } else {
 54:     SETERRQ(1,"Matrices are NOT equal");
 55:   }

 57:   MatStoreValues(A);
 58:   MatZeroEntries(A);
 59:   MatRetrieveValues(A);
 60:   MatEqual(A,C,&flg);
 61:   if (flg) {
 62:     PetscPrintf(PETSC_COMM_WORLD,"Matrices are equal\n");
 63:   } else {
 64:     SETERRQ(1,"Matrices are NOT equal");
 65:   }

 67:   MatDestroy(C);
 68:   MatDestroy(A);

 70:   PetscFinalize();
 71:   return 0;
 72: }

 74: