# VecGetArray4dWrite
Returns a pointer to a 4d contiguous array that will contain this processor's portion of the vector data.  You MUST call VecRestoreArray4dWrite() when you no longer need access to the array. 
## Synopsis
```
#include "petscvec.h"   
PetscErrorCode VecGetArray4dWrite(Vec x, PetscInt m, PetscInt n, PetscInt p, PetscInt q, PetscInt mstart, PetscInt nstart, PetscInt pstart, PetscInt qstart, PetscScalar ****a[])
```
Logically Collective


## Input Parameters

- ***x -*** the vector
- ***m -*** first dimension of four dimensional array
- ***n -*** second dimension of four dimensional array
- ***p -*** third dimension of four dimensional array
- ***q -*** fourth dimension of four dimensional array
- ***mstart -*** first index you will use in first coordinate direction (often 0)
- ***nstart -*** first index in the second coordinate direction (often 0)
- ***pstart -*** first index in the third coordinate direction (often 0)
- ***qstart -*** first index in the fourth coordinate direction (often 0)



## Output Parameter

- ***a -*** location to put pointer to the array





## Notes
For a vector obtained from DMCreateLocalVector() mstart, nstart, and pstart are likely
obtained from the corner indices obtained from DMDAGetGhostCorners() while for
DMCreateGlobalVector() they are the corner indices from DMDAGetCorners(). In both cases
the arguments from DMDAGet[Ghost]Corners() are reversed in the call to VecGetArray3d().

For standard PETSc vectors this is an inexpensive call; it does not copy the vector values.


## See Also
 `VecGetArray()`, `VecRestoreArray()`, `VecGetArrays()`, `VecGetArrayF90()`, `VecPlaceArray()`,
`VecRestoreArray2d()`, `DMDAVecGetarray()`, `DMDAVecRestoreArray()`, `VecGetArray3d()`, `VecRestoreArray3d()`,
`VecGetArray1d()`, `VecRestoreArray1d()`, `VecGetArray4d()`, `VecRestoreArray4d()`

## Level
beginner

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/interface/rvector.c.html#VecGetArray4dWrite">src/vec/vec/interface/rvector.c</A>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/vec/vec/interface/rvector.c)


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