Actual source code: ex88.c

petsc-3.9.2 2018-05-20
Report Typos and Errors

  2: static char help[] = "Tests MatShift(), MatScale(), and MatDiagonalScale() for SHELL and NEST matrices\n\n";

  4:  #include <petscmat.h>

  6: typedef struct _n_User *User;
  7: struct _n_User {
  8:   Mat B;
  9: };

 11: static PetscErrorCode MatView_User(Mat A,PetscViewer viewer)
 12: {
 13:   User           user;

 17:   MatShellGetContext(A,&user);
 18:   MatView(user->B,viewer);
 19:   return(0);
 20: }

 22: static PetscErrorCode MatMult_User(Mat A,Vec X,Vec Y)
 23: {
 24:   User           user;

 28:   MatShellGetContext(A,&user);
 29:   MatMult(user->B,X,Y);
 30:   return(0);
 31: }

 33: static PetscErrorCode MatMultTranspose_User(Mat A,Vec X,Vec Y)
 34: {
 35:   User           user;

 39:   MatShellGetContext(A,&user);
 40:   MatMultTranspose(user->B,X,Y);
 41:   return(0);
 42: }

 44: static PetscErrorCode MatGetDiagonal_User(Mat A,Vec X)
 45: {
 46:   User           user;

 50:   MatShellGetContext(A,&user);
 51:   MatGetDiagonal(user->B,X);
 52:   return(0);
 53: }

 55: static PetscErrorCode TestMatrix(Mat A,Vec X,Vec Y,Vec Z)
 56: {
 58:   Vec            W1,W2,diff;
 59:   Mat            E;
 60:   const char     *mattypename;
 61:   PetscViewer    viewer = PETSC_VIEWER_STDOUT_WORLD;
 62:   PetscScalar    diag[2] = {2.9678190300000000e+08,1.4173141580000000e+09};
 63:   PetscReal      nrm;
 64: 

 67:   VecDuplicate(X,&W1);
 68:   VecDuplicate(X,&W2);
 69:   MatScale(A,31);
 70:   MatShift(A,37);
 71:   MatDiagonalScale(A,X,Y);
 72:   MatScale(A,41);
 73:   MatDiagonalScale(A,Y,Z);
 74:   MatComputeExplicitOperator(A,&E);

 76:   PetscObjectGetType((PetscObject)A,&mattypename);
 77:   PetscViewerASCIIPrintf(viewer,"Matrix of type: %s\n",mattypename);
 78:   MatView(E,viewer);
 79:   MatMult(A,Z,W1);
 80:   MatMultTranspose(A,W1,W2);
 81:   VecView(W2,viewer);
 82:   MatGetDiagonal(A,W2);
 83:   VecCreateSeqWithArray(PETSC_COMM_SELF,1,2,diag,&diff);
 84:   VecAXPY(diff,-1.0,W2);
 85:   VecNorm(diff,NORM_2,&nrm);
 86:   if (nrm > PETSC_SMALL) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"MatGetDiagonal() produces incorrect result");
 87:   VecDestroy(&diff);
 88:   VecView(W2,viewer);

 90:   /* MATSHELL does not support MatDiagonalSet after MatScale */
 91:   if (strncmp(mattypename, "shell", 5)) {
 92:     MatDiagonalSet(A,X,INSERT_VALUES);
 93:     MatGetDiagonal(A,W1);
 94:     VecView(W1,viewer);
 95:   } else {
 96:     PetscViewerASCIIPrintf(viewer,"MatDiagonalSet not tested on MATSHELL\n");
 97:   }
 98:   MatDestroy(&E);
 99:   VecDestroy(&W1);
100:   VecDestroy(&W2);
101:   return(0);
102: }

104: int main(int argc,char **args)
105: {
106:   const PetscScalar xvals[] = {11,13},yvals[] = {17,19},zvals[] = {23,29};
107:   const PetscInt    inds[]  = {0,1};
108:   PetscScalar       avals[] = {2,3,5,7};
109:   Mat               A,S,D[4],N;
110:   Vec               X,Y,Z;
111:   User              user;
112:   PetscInt          i;
113:   PetscErrorCode    ierr;

115:   PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
116:   MatCreateSeqAIJ(PETSC_COMM_WORLD,2,2,2,NULL,&A);
117:   MatSetUp(A);
118:   MatSetValues(A,2,inds,2,inds,avals,INSERT_VALUES);
119:   VecCreateSeq(PETSC_COMM_WORLD,2,&X);
120:   VecDuplicate(X,&Y);
121:   VecDuplicate(X,&Z);
122:   VecSetValues(X,2,inds,xvals,INSERT_VALUES);
123:   VecSetValues(Y,2,inds,yvals,INSERT_VALUES);
124:   VecSetValues(Z,2,inds,zvals,INSERT_VALUES);
125:   MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
126:   MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
127:   VecAssemblyBegin(X);
128:   VecAssemblyBegin(Y);
129:   VecAssemblyBegin(Z);
130:   VecAssemblyEnd(X);
131:   VecAssemblyEnd(Y);
132:   VecAssemblyEnd(Z);

134:   PetscNew(&user);
135:   user->B = A;

137:   MatCreateShell(PETSC_COMM_WORLD,2,2,2,2,user,&S);
138:   MatSetUp(S);
139:   MatShellSetOperation(S,MATOP_VIEW,(void (*)(void))MatView_User);
140:   MatShellSetOperation(S,MATOP_MULT,(void (*)(void))MatMult_User);
141:   MatShellSetOperation(S,MATOP_MULT_TRANSPOSE,(void (*)(void))MatMultTranspose_User);
142:   MatShellSetOperation(S,MATOP_GET_DIAGONAL,(void (*)(void))MatGetDiagonal_User);

144:   for (i=0; i<4; i++) {
145:     MatCreateSeqDense(PETSC_COMM_WORLD,1,1,&avals[i],&D[i]);
146:   }
147:   MatCreateNest(PETSC_COMM_WORLD,2,NULL,2,NULL,D,&N);
148:   MatSetUp(N);

150:   TestMatrix(S,X,Y,Z);
151:   TestMatrix(A,X,Y,Z);
152:   TestMatrix(N,X,Y,Z);

154:   for (i=0; i<4; i++) {MatDestroy(&D[i]);}
155:   MatDestroy(&A);
156:   MatDestroy(&S);
157:   MatDestroy(&N);
158:   VecDestroy(&X);
159:   VecDestroy(&Y);
160:   VecDestroy(&Z);
161:   PetscFree(user);
162:   PetscFinalize();
163:   return ierr;
164: }


167: /*TEST

169:    test:

171: TEST*/