petsc-3.3-p7 2013-05-11

MatGetArray

Returns a pointer to the element values in the matrix. The result of this routine is dependent on the underlying matrix data structure, and may not even work for certain matrix types. You MUST call MatRestoreArray() when you no longer need to access the array.

Synopsis

#include "petscmat.h" 
PetscErrorCode  MatGetArray(Mat mat,PetscScalar *v[])

Not Collective

Input Parameter

mat -the matrix

Output Parameter

v -the location of the values

Fortran Note

This routine is used differently from Fortran, e.g.,

        Mat         mat
        PetscScalar mat_array(1)
        PetscOffset i_mat
        PetscErrorCode ierr
        call MatGetArray(mat,mat_array,i_mat,ierr)

  C  Access first local entry in matrix; note that array is
  C  treated as one dimensional
        value = mat_array(i_mat + 1)

        [... other code ...]
        call MatRestoreArray(mat,mat_array,i_mat,ierr)

See the <a href="../../docs/manual.pdf#Chapter 9 PETSc for Fortran Users">Fortran chapter of the users manual</a> and src/mat/examples/tests for details.

Examples