1 2 static char help[] = "Tests the use of MatZeroRows() for uniprocessor matrices.\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,five = 5.0; 12 IS isrow; 13 PetscBool keepnonzeropattern; 14 15 ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 16 /* create the matrix for the five point stencil, YET AGAIN*/ 17 ierr = MatCreate(PETSC_COMM_SELF,&C);CHKERRQ(ierr); 18 ierr = MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n);CHKERRQ(ierr); 19 ierr = MatSetFromOptions(C);CHKERRQ(ierr); 20 ierr = MatSetUp(C);CHKERRQ(ierr); 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 = ISCreateStride(PETSC_COMM_SELF,(m*n)/2,0,2,&isrow);CHKERRQ(ierr); 35 36 ierr = PetscOptionsHasName(NULL,NULL,"-keep_nonzero_pattern",&keepnonzeropattern);CHKERRQ(ierr); 37 if (keepnonzeropattern) { 38 ierr = MatSetOption(C,MAT_KEEP_NONZERO_PATTERN,PETSC_TRUE);CHKERRQ(ierr); 39 } 40 41 ierr = MatZeroRowsIS(C,isrow,five,0,0);CHKERRQ(ierr); 42 43 ierr = MatView(C,PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr); 44 45 ierr = ISDestroy(&isrow);CHKERRQ(ierr); 46 ierr = MatDestroy(&C);CHKERRQ(ierr); 47 ierr = PetscFinalize(); 48 return ierr; 49 } 50 51 /*TEST 52 53 test: 54 55 test: 56 suffix: 2 57 args: -mat_type seqbaij -mat_block_size 5 58 59 test: 60 suffix: 3 61 args: -keep_nonzero_pattern 62 63 test: 64 suffix: 4 65 args: -keep_nonzero_pattern -mat_type seqbaij -mat_block_size 5 66 67 TEST*/ 68