1 2 static char help[] = "Tests the use of MatSolveTranspose().\n\n"; 3 4 #include <petscmat.h> 5 6 int main(int argc,char **args) 7 { 8 Mat C,A; 9 PetscInt i,j,m = 5,n = 5,Ii,J; 10 PetscErrorCode ierr; 11 PetscScalar v,five = 5.0,one = 1.0; 12 IS isrow,row,col; 13 Vec x,u,b; 14 PetscReal norm; 15 MatFactorInfo info; 16 17 ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 18 ierr = PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL);CHKERRQ(ierr); 19 ierr = PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);CHKERRQ(ierr); 20 21 ierr = MatCreateSeqAIJ(PETSC_COMM_SELF,m*n,m*n,5,NULL,&C);CHKERRQ(ierr); 22 ierr = MatSetUp(C);CHKERRQ(ierr); 23 24 /* create the matrix for the five point stencil, YET AGAIN*/ 25 for (i=0; i<m; i++) { 26 for (j=0; j<n; j++) { 27 v = -1.0; Ii = j + n*i; 28 if (i>0) {J = Ii - n; ierr = MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 29 if (i<m-1) {J = Ii + n; ierr = MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 30 if (j>0) {J = Ii - 1; ierr = MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 31 if (j<n-1) {J = Ii + 1; ierr = MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 32 v = 4.0; ierr = MatSetValues(C,1,&Ii,1,&Ii,&v,INSERT_VALUES);CHKERRQ(ierr); 33 } 34 } 35 ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 36 ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 37 38 ierr = ISCreateStride(PETSC_COMM_SELF,(m*n)/2,0,2,&isrow);CHKERRQ(ierr); 39 ierr = MatZeroRowsIS(C,isrow,five,0,0);CHKERRQ(ierr); 40 41 ierr = VecCreateSeq(PETSC_COMM_SELF,m*n,&u);CHKERRQ(ierr); 42 ierr = VecDuplicate(u,&x);CHKERRQ(ierr); 43 ierr = VecDuplicate(u,&b);CHKERRQ(ierr); 44 ierr = VecSet(u,one);CHKERRQ(ierr); 45 46 ierr = MatMultTranspose(C,u,b);CHKERRQ(ierr); 47 48 /* Set default ordering to be Quotient Minimum Degree; also read 49 orderings from the options database */ 50 ierr = MatGetOrdering(C,MATORDERINGQMD,&row,&col);CHKERRQ(ierr); 51 52 ierr = MatFactorInfoInitialize(&info);CHKERRQ(ierr); 53 ierr = MatGetFactor(C,MATSOLVERPETSC,MAT_FACTOR_LU,&A);CHKERRQ(ierr); 54 ierr = MatLUFactorSymbolic(A,C,row,col,&info);CHKERRQ(ierr); 55 ierr = MatLUFactorNumeric(A,C,&info);CHKERRQ(ierr); 56 ierr = MatSolveTranspose(A,b,x);CHKERRQ(ierr); 57 58 ierr = ISView(row,PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr); 59 ierr = VecAXPY(x,-1.0,u);CHKERRQ(ierr); 60 ierr = VecNorm(x,NORM_2,&norm);CHKERRQ(ierr); 61 ierr = PetscPrintf(PETSC_COMM_SELF,"Norm of error %g\n",(double)norm);CHKERRQ(ierr); 62 63 ierr = ISDestroy(&row);CHKERRQ(ierr); 64 ierr = ISDestroy(&col);CHKERRQ(ierr); 65 ierr = ISDestroy(&isrow);CHKERRQ(ierr); 66 ierr = VecDestroy(&u);CHKERRQ(ierr); 67 ierr = VecDestroy(&x);CHKERRQ(ierr); 68 ierr = VecDestroy(&b);CHKERRQ(ierr); 69 ierr = MatDestroy(&C);CHKERRQ(ierr); 70 ierr = MatDestroy(&A);CHKERRQ(ierr); 71 ierr = PetscFinalize(); 72 return ierr; 73 } 74 75 76 /*TEST 77 78 test: 79 80 TEST*/ 81