:orphan:
# MatSeqSBAIJSetPreallocationCSR
Creates a sparse parallel matrix in `MATSEQSBAIJ` format using the given nonzero structure and (optional) numerical values 
## Synopsis
```
#include "petscmat.h" 
PetscErrorCode MatSeqSBAIJSetPreallocationCSR(Mat B, PetscInt bs, const PetscInt i[], const PetscInt j[], const PetscScalar v[])
```

## Input Parameters

- ***B -*** the matrix
- ***bs -*** size of block, the blocks are ALWAYS square.
- ***i -*** the indices into j for the start of each local row (starts with zero)
- ***j -*** the column indices for each local row (starts with zero) these must be sorted for each row
- ***v -*** optional values in the matrix





## Notes
The order of the entries in values is specified by the `MatOption` `MAT_ROW_ORIENTED`.  For example, C programs
may want to use the default `MAT_ROW_ORIENTED` = `PETSC_TRUE` and use an array v[nnz][bs][bs] where the second index is
over rows within a block and the last index is over columns within a block row.  Fortran programs will likely set
`MAT_ROW_ORIENTED` = `PETSC_FALSE` and use a Fortran array v(bs,bs,nnz) in which the first index is over rows within a
block column and the second index is over columns within a block.

Any entries below the diagonal are ignored

Though this routine has Preallocation() in the name it also sets the exact nonzero locations of the matrix entries
and usually the numerical values as well


## See Also
 [](ch_matrices), `Mat`, `MATSEQSBAIJ`, `MatCreate()`, `MatCreateSeqSBAIJ()`, `MatSetValuesBlocked()`, `MatSeqSBAIJSetPreallocation()`, `MATSEQSBAIJ`

## Level
advanced

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

## Implementations

<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/sbaij/seq/sbaij.c.html#MatSeqSBAIJSetPreallocationCSR_SeqSBAIJ">MatSeqSBAIJSetPreallocationCSR_SeqSBAIJ in src/mat/impls/sbaij/seq/sbaij.c</A><BR>


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


[Index of all Mat routines](index.md)  
[Table of Contents for all manual pages](/manualpages/index.md)  
[Index of all manual pages](/manualpages/singleindex.md)