# DAGetMatrix

Creates a matrix with the correct parallel layout and nonzero structure required for computing the Jacobian on a function defined using the stencil set in the DA.

### Synopsis

    #include "petscda.h"
    #include "petscmat.h"
    PetscErrorCode PETSCDM_DLLEXPORT DAGetMatrix(DA da, MatType mtype,Mat *J)

Collective on DA

### Input Parameter

| da | - the distributed array
| mtype | - Supported types are MATSEQAIJ, MATMPIAIJ, MATSEQBAIJ, MATMPIBAIJ, MATSEQSBAIJ, MATMPISBAIJ, or any type which inherits from one of these (such as MATAIJ, MATLUSOL, etc.).

### Output Parameters

J -matrix with the correct nonzero structure (obviously without the correct Jacobian values)

Notes: This properly preallocates the number of nonzeros in the sparse matrix so you do not need to do it yourself.

### See Also

ISColoringView(), ISColoringGetIS(), MatFDColoringCreate(), DASetBlockFills()

Level:advanced
Location:src/dm/da/utils/fdda.c
Index of all DA routines
Table of Contents for all manual pages
Index of all manual pages

### Examples

src/snes/examples/tutorials/ex5.c.html
src/snes/examples/tutorials/ex14.c.html
src/snes/examples/tutorials/ex24.c.html
src/snes/examples/tutorials/ex26.c.html
src/snes/examples/tutorials/ex5f.F.html
src/snes/examples/tutorials/ex5f90.F.html
src/ts/examples/tutorials/ex7.c.html