1 /* 2 * ex195.c 3 * 4 * Created on: Aug 24, 2015 5 * Author: Fande Kong <fdkong.jd@gmail.com> 6 */ 7 8 static char help[] = " Demonstrate the use of MatConvert_Nest_AIJ\n"; 9 10 #include <petscmat.h> 11 12 13 int main(int argc,char **args) 14 { 15 Mat A1,A2,A3,A4,A5,B,C,C1,nest; 16 Mat mata[4]; 17 Mat aij; 18 MPI_Comm comm; 19 PetscInt m,M,n,istart,iend,ii,i,J,j,K=10; 20 PetscScalar v; 21 PetscMPIInt size; 22 PetscErrorCode ierr; 23 PetscBool equal; 24 25 ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 26 comm = PETSC_COMM_WORLD; 27 ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr); 28 29 /* 30 Assemble the matrix for the five point stencil, YET AGAIN 31 */ 32 ierr = MatCreate(comm,&A1);CHKERRQ(ierr); 33 m=2,n=2; 34 ierr = MatSetSizes(A1,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n);CHKERRQ(ierr); 35 ierr = MatSetFromOptions(A1);CHKERRQ(ierr); 36 ierr = MatSetUp(A1);CHKERRQ(ierr); 37 ierr = MatGetOwnershipRange(A1,&istart,&iend);CHKERRQ(ierr); 38 for (ii=istart; ii<iend; ii++) { 39 v = -1.0; i = ii/n; j = ii - i*n; 40 if (i>0) {J = ii - n; ierr = MatSetValues(A1,1,&ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 41 if (i<m-1) {J = ii + n; ierr = MatSetValues(A1,1,&ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 42 if (j>0) {J = ii - 1; ierr = MatSetValues(A1,1,&ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 43 if (j<n-1) {J = ii + 1; ierr = MatSetValues(A1,1,&ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);} 44 v = 4.0; ierr = MatSetValues(A1,1,&ii,1,&ii,&v,INSERT_VALUES);CHKERRQ(ierr); 45 } 46 ierr = MatAssemblyBegin(A1,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 47 ierr = MatAssemblyEnd(A1,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 48 ierr = MatView(A1,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 49 50 ierr = MatDuplicate(A1,MAT_COPY_VALUES,&A2);CHKERRQ(ierr); 51 ierr = MatDuplicate(A1,MAT_COPY_VALUES,&A3);CHKERRQ(ierr); 52 ierr = MatDuplicate(A1,MAT_COPY_VALUES,&A4);CHKERRQ(ierr); 53 54 /*create a nest matrix */ 55 ierr = MatCreate(comm,&nest);CHKERRQ(ierr); 56 ierr = MatSetType(nest,MATNEST);CHKERRQ(ierr); 57 mata[0]=A1,mata[1]=A2,mata[2]=A3,mata[3]=A4; 58 ierr = MatNestSetSubMats(nest,2,NULL,2,NULL,mata);CHKERRQ(ierr); 59 ierr = MatSetUp(nest);CHKERRQ(ierr); 60 ierr = MatConvert(nest,MATAIJ,MAT_INITIAL_MATRIX,&aij);CHKERRQ(ierr); 61 ierr = MatView(aij,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 62 63 /* create a dense matrix */ 64 ierr = MatGetSize(nest,&M,NULL);CHKERRQ(ierr); 65 ierr = MatGetLocalSize(nest,&m,NULL);CHKERRQ(ierr); 66 ierr = MatCreateDense(comm,m,PETSC_DECIDE,M,K,NULL,&B);CHKERRQ(ierr); 67 ierr = MatSetRandom(B,PETSC_NULL);CHKERRQ(ierr); 68 ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 69 ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 70 71 /* C = nest*B_dense */ 72 ierr = MatMatMult(nest,B,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&C);CHKERRQ(ierr); 73 ierr = MatMatMult(nest,B,MAT_REUSE_MATRIX,PETSC_DEFAULT,&C);CHKERRQ(ierr); 74 ierr = MatMatMultEqual(nest,B,C,10,&equal);CHKERRQ(ierr); 75 if (!equal) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_PLIB,"Error in C != nest*B_dense"); 76 ierr = MatDestroy(&nest);CHKERRQ(ierr); 77 78 if (size > 1) { /* Do not know why this test fails for size = 1 */ 79 ierr = MatCreateTranspose(A1,&A5);CHKERRQ(ierr); /* A1 is symmetric */ 80 mata[0] = A5; 81 ierr = MatCreate(comm,&nest);CHKERRQ(ierr); 82 ierr = MatSetType(nest,MATNEST);CHKERRQ(ierr); 83 ierr = MatNestSetSubMats(nest,2,NULL,2,NULL,mata);CHKERRQ(ierr); 84 ierr = MatSetUp(nest);CHKERRQ(ierr); 85 ierr = MatMatMult(nest,B,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&C1);CHKERRQ(ierr); 86 ierr = MatMatMult(nest,B,MAT_REUSE_MATRIX,PETSC_DEFAULT,&C1);CHKERRQ(ierr); 87 88 ierr = MatEqual(C1,C,&equal);CHKERRQ(ierr); 89 if (!equal) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_PLIB,"Error in C1 != C"); 90 ierr = MatDestroy(&C1);CHKERRQ(ierr); 91 ierr = MatDestroy(&A5);CHKERRQ(ierr); 92 } 93 94 ierr = MatDestroy(&C);CHKERRQ(ierr); 95 ierr = MatDestroy(&B);CHKERRQ(ierr); 96 ierr = MatDestroy(&nest);CHKERRQ(ierr); 97 ierr = MatDestroy(&aij);CHKERRQ(ierr); 98 ierr = MatDestroy(&A1);CHKERRQ(ierr); 99 ierr = MatDestroy(&A2);CHKERRQ(ierr); 100 ierr = MatDestroy(&A3);CHKERRQ(ierr); 101 ierr = MatDestroy(&A4);CHKERRQ(ierr); 102 ierr = PetscFinalize(); 103 return ierr; 104 } 105 106 107 /*TEST 108 109 test: 110 nsize: 2 111 112 TEST*/ 113