xref: /petsc/src/mat/impls/transpose/transm.c (revision 7c4f633dc6bb6149cca88d301ead35a99e103cbb)

#define PETSCMAT_DLL

#include "private/matimpl.h"          /*I "petscmat.h" I*/

typedef struct {
  Mat A;
  Vec w;
} Mat_Transpose;

#undef __FUNCT__
#define __FUNCT__ "MatMult_Transpose"
PetscErrorCode MatMult_Transpose(Mat N,Vec x,Vec y)
{
  Mat_Transpose  *Na = (Mat_Transpose*)N->data;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  ierr = MatMultTranspose(Na->A,x,y);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "MatMultAdd_Transpose"
PetscErrorCode MatMultAdd_Transpose(Mat N,Vec v1,Vec v2,Vec v3)
{
  Mat_Transpose  *Na = (Mat_Transpose*)N->data;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  ierr = MatMultTransposeAdd(Na->A,v1,v2,v3);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "MatDestroy_Transpose"
PetscErrorCode MatDestroy_Transpose(Mat N)
{
  Mat_Transpose  *Na = (Mat_Transpose*)N->data;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  if (Na->A) { ierr = MatDestroy(Na->A);CHKERRQ(ierr); }
  ierr = PetscFree(Na);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "MatCreateTranspose"
/*@
      MatCreateTranspose - Creates a new matrix object that behaves like A'

   Collective on Mat

   Input Parameter:
.   A  - the (possibly rectangular) matrix

   Output Parameter:
.   N - the matrix that represents A'

   Level: intermediate

   Notes: The transpose A' is NOT actually formed! Rather the new matrix
          object performs the matrix-vector product by using the MatMultTranspose() on
          the original matrix

.seealso: MatCreateNormal(), MatMult(), MatMultTranspose(), MatCreate()

@*/
PetscErrorCode PETSCMAT_DLLEXPORT MatCreateTranspose(Mat A,Mat *N)
{
  PetscErrorCode ierr;
  PetscInt       m,n;
  Mat_Transpose  *Na;

  PetscFunctionBegin;
  ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
  ierr = MatCreate(((PetscObject)A)->comm,N);CHKERRQ(ierr);
  ierr = MatSetSizes(*N,n,m,PETSC_DECIDE,PETSC_DECIDE);CHKERRQ(ierr);
  ierr = PetscObjectChangeTypeName((PetscObject)*N,MATTRANSPOSEMAT);CHKERRQ(ierr);

  ierr      = PetscNewLog(*N,Mat_Transpose,&Na);CHKERRQ(ierr);
  (*N)->data = (void*) Na;
  ierr      = PetscObjectReference((PetscObject)A);CHKERRQ(ierr);
  Na->A     = A;

  (*N)->ops->destroy     = MatDestroy_Transpose;
  (*N)->ops->mult        = MatMult_Transpose;
  (*N)->ops->multadd     = MatMultAdd_Transpose;
  (*N)->assembled        = PETSC_TRUE;

  (*N)->rmap->bs = (*N)->cmap->bs = A->rmap->bs;
  ierr = PetscMapSetUp((*N)->rmap);CHKERRQ(ierr);
  ierr = PetscMapSetUp((*N)->cmap);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}