Actual source code: ex41.c

  1: static char help[] = "Nest vector set subvector functionality.\n\n";

  3: /*T
  4:    Concepts: vectors^block operators
  5:    Concepts: vectors^setting values
  6:    Concepts: vectors^local access to
  7:    Processors: n
  8: T*/

 10: #include <petscvec.h>

 12: PetscErrorCode test_vec_ops(void)
 13: {
 14:   Vec            X,Y,a,b;
 15:   Vec            c,d,e,f,g,h;
 16:   PetscScalar    val;
 17:   PetscInt       tmp_ind[2];
 18:   Vec            tmp_buf[2];

 20:   PetscPrintf(PETSC_COMM_WORLD, "============== %s ==============\n",PETSC_FUNCTION_NAME);

 22:   /* create 4 worker vectors */
 23:   VecCreate(PETSC_COMM_WORLD, &c);
 24:   VecSetSizes(c, PETSC_DECIDE, 4);
 25:   VecSetType(c, VECMPI);
 26:   VecDuplicate(c, &d);
 27:   VecDuplicate(c, &e);
 28:   VecDuplicate(c, &f);

 30:   /* create two more workers of different sizes */
 31:   VecCreate(PETSC_COMM_WORLD, &g);
 32:   VecSetSizes(g, PETSC_DECIDE, 6);
 33:   VecSetType(g, VECMPI);
 34:   VecCreate(PETSC_COMM_WORLD, &h);
 35:   VecSetSizes(h, PETSC_DECIDE, 8);
 36:   VecSetType(h, VECMPI);

 38:   /* set the 6 vectors to some numbers */
 39:   VecSet(c, 1.0);
 40:   VecSet(d, 2.0);
 41:   VecSet(e, 3.0);
 42:   VecSet(f, 4.0);
 43:   VecSet(g, 5.0);
 44:   VecSet(h, 6.0);

 46:   /* assemble a */
 47:   PetscPrintf(PETSC_COMM_WORLD, "a = [c d] \n");
 48:   tmp_buf[0] = c; tmp_buf[1] = d;

 50:   VecCreateNest(PETSC_COMM_WORLD,2,NULL,tmp_buf,&a);
 51:   VecView(a,PETSC_VIEWER_STDOUT_WORLD);
 52:   PetscPrintf(PETSC_COMM_WORLD, "a = [d c] \n");
 53:   VecNestSetSubVec(a, 1, c);
 54:   VecNestSetSubVec(a, 0, d);
 55:   VecAssemblyBegin(a);
 56:   VecAssemblyEnd(a);
 57:   VecView(a,PETSC_VIEWER_STDOUT_WORLD);

 59:   /* assemble b */
 60:   PetscPrintf(PETSC_COMM_WORLD, "b = [e f] \n");
 61:   tmp_buf[0] = e; tmp_buf[1] = f;

 63:   VecCreateNest(PETSC_COMM_WORLD,2,NULL,tmp_buf,&b);
 64:   VecView(b,PETSC_VIEWER_STDOUT_WORLD);
 65:   PetscPrintf(PETSC_COMM_WORLD, "b = [f e] \n");
 66:   VecNestSetSubVec(b, 1, e);
 67:   VecNestSetSubVec(b, 0, f);
 68:   VecAssemblyBegin(b);
 69:   VecAssemblyEnd(b);
 70:   VecView(b,PETSC_VIEWER_STDOUT_WORLD);

 72:   PetscPrintf(PETSC_COMM_WORLD, "X = [a b] \n");
 73:   tmp_buf[0] = a; tmp_buf[1] = b;

 75:   VecCreateNest(PETSC_COMM_WORLD,2,NULL,tmp_buf,&X);
 76:   VecView(X,PETSC_VIEWER_STDOUT_WORLD);
 77:   VecDot(X,X, &val);
 78:   PetscPrintf(PETSC_COMM_WORLD, "X.X = %g \n", (double)PetscRealPart(val));

 80:   PetscPrintf(PETSC_COMM_WORLD, "X = [b a] \n");
 81:   /* re-order components of X */
 82:   VecNestSetSubVec(X,1,a);
 83:   VecNestSetSubVec(X,0,b);
 84:   VecAssemblyBegin(X);
 85:   VecAssemblyEnd(X);
 86:   VecView(X,PETSC_VIEWER_STDOUT_WORLD);
 87:   VecDot(X,X,&val);
 88:   PetscPrintf(PETSC_COMM_WORLD, "X.X = %g \n", (double)PetscRealPart(val));

 90:   /* re-assemble X */
 91:   PetscPrintf(PETSC_COMM_WORLD, "X = [g h] \n");
 92:   VecNestSetSubVec(X,1,g);
 93:   VecNestSetSubVec(X,0,h);
 94:   VecAssemblyBegin(X);
 95:   VecAssemblyEnd(X);
 96:   VecView(X,PETSC_VIEWER_STDOUT_WORLD);
 97:   VecDot(X,X,&val);
 98:   PetscPrintf(PETSC_COMM_WORLD, "X.X = %g \n", (double)PetscRealPart(val));

100:   PetscPrintf(PETSC_COMM_WORLD, "Y = X \n");
101:   VecDuplicate(X, &Y);
102:   VecCopy(X,Y);
103:   VecView(Y,PETSC_VIEWER_STDOUT_WORLD);
104:   VecDot(Y,Y,&val);
105:   PetscPrintf(PETSC_COMM_WORLD, "Y.Y = %g \n", (double)PetscRealPart(val));

107:   PetscPrintf(PETSC_COMM_WORLD, "Y = [a b] \n");
108:   tmp_buf[0] = a; tmp_buf[1] = b;
109:   tmp_ind[0] = 0; tmp_ind[1] = 1;

111:   VecNestSetSubVecs(Y,2,tmp_ind,tmp_buf);
112:   VecView(Y,PETSC_VIEWER_STDOUT_WORLD);

114:   VecDestroy(&c);
115:   VecDestroy(&d);
116:   VecDestroy(&e);
117:   VecDestroy(&f);
118:   VecDestroy(&g);
119:   VecDestroy(&h);
120:   VecDestroy(&a);
121:   VecDestroy(&b);
122:   VecDestroy(&X);
123:   VecDestroy(&Y);
124:   return 0;
125: }

127: int main(int argc, char **args)
128: {

130:   PetscInitialize(&argc, &args,(char*)0, help);
131:   test_vec_ops();
132:   PetscFinalize();
133:   return 0;
134: }

136: /*TEST

138:    test:

140: TEST*/