1 2 #include "src/mat/matimpl.h" /*I "petscmat.h" I*/ 3 4 typedef struct { 5 Mat A; 6 Vec w; 7 } Mat_Normal; 8 9 #undef __FUNCT__ 10 #define __FUNCT__ "MatMult_Normal" 11 int MatMult_Normal(Mat N,Vec x,Vec y) 12 { 13 Mat_Normal *Na = (Mat_Normal*)N->data; 14 int ierr; 15 16 PetscFunctionBegin; 17 ierr = MatMult(Na->A,x,Na->w);CHKERRQ(ierr); 18 ierr = MatMultTranspose(Na->A,Na->w,y);CHKERRQ(ierr); 19 PetscFunctionReturn(0); 20 } 21 22 #undef __FUNCT__ 23 #define __FUNCT__ "MatDestroy_Normal" 24 int MatDestroy_Normal(Mat N) 25 { 26 Mat_Normal *Na = (Mat_Normal*)N->data; 27 int ierr; 28 29 PetscFunctionBegin; 30 ierr = PetscObjectDereference((PetscObject)Na->A);CHKERRQ(ierr); 31 ierr = VecDestroy(Na->w);CHKERRQ(ierr); 32 ierr = PetscFree(Na);CHKERRQ(ierr); 33 PetscFunctionReturn(0); 34 } 35 36 /* 37 Slow, nonscalable version 38 */ 39 #undef __FUNCT__ 40 #define __FUNCT__ "MatGetDiagonal_Normal" 41 int MatGetDiagonal_Normal(Mat N,Vec v) 42 { 43 Mat_Normal *Na = (Mat_Normal*)N->data; 44 Mat A = Na->A; 45 int ierr,i,j,rstart,rend,nnz,*cols; 46 PetscScalar *diag,*work,*values; 47 PetscMap cmap; 48 49 PetscFunctionBegin; 50 ierr = PetscMalloc(2*A->N*sizeof(PetscScalar),&diag);CHKERRQ(ierr); 51 work = diag + A->N; 52 ierr = PetscMemzero(work,A->N*sizeof(PetscScalar));CHKERRQ(ierr); 53 ierr = MatGetOwnershipRange(A,&rstart,&rend);CHKERRQ(ierr); 54 for (i=rstart; i<rend; i++) { 55 ierr = MatGetRow(A,i,&nnz,&cols,&values);CHKERRQ(ierr); 56 for (j=0; j<nnz; j++) { 57 work[cols[j]] += values[j]*values[j]; 58 } 59 ierr = MatRestoreRow(A,i,&nnz,&cols,&values);CHKERRQ(ierr); 60 } 61 ierr = MPI_Allreduce(work,diag,A->N,MPIU_SCALAR,MPI_SUM,N->comm);CHKERRQ(ierr); 62 ierr = MatGetPetscMaps(A,PETSC_NULL,&cmap);CHKERRQ(ierr); 63 ierr = PetscMapGetLocalRange(cmap,&rstart,&rend);CHKERRQ(ierr); 64 ierr = VecGetArray(v,&values);CHKERRQ(ierr); 65 ierr = PetscMemcpy(values,diag+rstart,(rend-rstart)*sizeof(PetscScalar));CHKERRQ(ierr); 66 ierr = VecRestoreArray(v,&values);CHKERRQ(ierr); 67 ierr = PetscFree(diag);CHKERRQ(ierr); 68 PetscFunctionReturn(0); 69 } 70 71 #undef __FUNCT__ 72 #define __FUNCT__ "MatCreateNormal" 73 /*@ 74 MatCreateNormal - Creates a new matrix object that behaves like A'*A. 75 76 Collective on Mat 77 78 Input Parameter: 79 . A - the (possibly rectangular) matrix 80 81 Output Parameter: 82 . N - the matrix that represents A'*A 83 84 Notes: The product A'*A is NOT actually formed! Rather the new matrix 85 object performs the matrix-vector product by first multiplying by 86 A and then A' 87 @*/ 88 int MatCreateNormal(Mat A,Mat *N) 89 { 90 int ierr,m,n; 91 Mat_Normal *Na; 92 93 PetscFunctionBegin; 94 ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr); 95 ierr = MatCreate(A->comm,n,n,PETSC_DECIDE,PETSC_DECIDE,N);CHKERRQ(ierr); 96 ierr = PetscObjectChangeTypeName((PetscObject)*N,MATNORMAL);CHKERRQ(ierr); 97 98 ierr = PetscNew(Mat_Normal,&Na);CHKERRQ(ierr); 99 Na->A = A; 100 ierr = PetscObjectReference((PetscObject)A);CHKERRQ(ierr); 101 (*N)->data = (void*) Na; 102 103 ierr = VecCreateMPI(A->comm,m,PETSC_DECIDE,&Na->w);CHKERRQ(ierr); 104 (*N)->ops->destroy = MatDestroy_Normal; 105 (*N)->ops->mult = MatMult_Normal; 106 (*N)->ops->getdiagonal = MatGetDiagonal_Normal; 107 (*N)->assembled = PETSC_TRUE; 108 (*N)->N = A->N; 109 (*N)->M = A->N; 110 (*N)->n = A->n; 111 (*N)->m = A->n; 112 PetscFunctionReturn(0); 113 } 114 115