1 2 static char help[] = "Tests reordering a matrix.\n\n"; 3 4 #include <petscmat.h> 5 6 int main(int argc,char **args) 7 { 8 Mat C; 9 PetscInt i,j,m = 5,n = 5,Ii,J; 10 PetscErrorCode ierr; 11 PetscScalar v; 12 IS perm,iperm; 13 14 ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 15 ierr = MatCreate(PETSC_COMM_SELF,&C);CHKERRQ(ierr); 16 ierr = MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n);CHKERRQ(ierr); 17 ierr = MatSetFromOptions(C);CHKERRQ(ierr); 18 ierr = MatSetUp(C);CHKERRQ(ierr); 19 20 /* create the matrix for the five point stencil, YET AGAIN*/ 21 for (i=0; i<m; i++) { 22 for (j=0; j<n; j++) { 23 v = -1.0; Ii = j + n*i; 24 if (i>0) {J = Ii - n; ierr = MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 25 if (i<m-1) {J = Ii + n; ierr = MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 26 if (j>0) {J = Ii - 1; ierr = MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 27 if (j<n-1) {J = Ii + 1; ierr = MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 28 v = 4.0; ierr = MatSetValues(C,1,&Ii,1,&Ii,&v,INSERT_VALUES);CHKERRQ(ierr); 29 } 30 } 31 ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 32 ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 33 34 ierr = MatGetOrdering(C,MATORDERINGND,&perm,&iperm);CHKERRQ(ierr); 35 ierr = ISView(perm,PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr); 36 ierr = ISView(iperm,PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr); 37 ierr = MatView(C,PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr); 38 39 ierr = ISDestroy(&perm);CHKERRQ(ierr); 40 ierr = ISDestroy(&iperm);CHKERRQ(ierr); 41 ierr = MatDestroy(&C);CHKERRQ(ierr); 42 ierr = PetscFinalize(); 43 return ierr; 44 } 45 46 47 /*TEST 48 49 test: 50 51 TEST*/ 52