:orphan:
# MatSeqAIJGetCSRAndMemType
Get the CSR arrays and the memory type of the `MATSEQAIJ` matrix 
## Synopsis
```
#include "petscmat.h" 
PetscErrorCode MatSeqAIJGetCSRAndMemType(Mat mat, const PetscInt **i, const PetscInt **j, PetscScalar **a, PetscMemType *mtype)
```
Not Collective; No Fortran Support


## Input Parameter

- ***mat -*** a matrix of type `MATSEQAIJ` or its subclasses



## Output Parameters

- ***i -*** row map array of the matrix
- ***j -*** column index array of the matrix
- ***a -*** data array of the matrix
- ***memtype -*** memory type of the arrays





## Notes
Any of the output parameters can be `NULL`, in which case the corresponding value is not returned.
If mat is a device matrix, the arrays are on the device. Otherwise, they are on the host.

One can call this routine on a preallocated but not assembled matrix to just get the memory of the CSR underneath the matrix.
If the matrix is assembled, the data array `a` is guaranteed to have the latest values of the matrix.


## See Also
 [](ch_matrices), `Mat`, `MatSeqAIJGetArray()`, `MatSeqAIJGetArrayRead()`

## Level
Developer

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/aij/seq/aij.c.html#MatSeqAIJGetCSRAndMemType">src/mat/impls/aij/seq/aij.c</A>

## Implementations

<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/aij/seq/kokkos/aijkok.kokkos.cxx.html#MatSeqAIJGetCSRAndMemType_SeqAIJKokkos">MatSeqAIJGetCSRAndMemType_SeqAIJKokkos in src/mat/impls/aij/seq/kokkos/aijkok.kokkos.cxx</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/aij/seq/seqcusparse/aijcusparse.cu.html#MatSeqAIJGetCSRAndMemType_SeqAIJCUSPARSE">MatSeqAIJGetCSRAndMemType_SeqAIJCUSPARSE in src/mat/impls/aij/seq/seqcusparse/aijcusparse.cu</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/aij/seq/seqhipsparse/aijhipsparse.hip.c.html#MatSeqAIJGetCSRAndMemType_SeqAIJHIPSPARSE">MatSeqAIJGetCSRAndMemType_SeqAIJHIPSPARSE in src/mat/impls/aij/seq/seqhipsparse/aijhipsparse.hip.c</A><BR>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/mat/impls/aij/seq/aij.c)


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