# PetscBLASIntCast
casts a `PetscInt` (which may be 64 bits in size) to a `PetscBLASInt` (which may be 32 bits in size), generates an error if the `PetscBLASInt` is not large enough to hold the number. 
## Synopsis
```
static inline PetscErrorCode PetscBLASIntCast(PetscInt a, PetscBLASInt *b)
```
Not Collective


## Input Parameter

- ***a -*** the `PetscInt` value



## Output Parameter

- ***b -*** the resulting `PetscBLASInt` value





## Notes
Not available from Fortran

Errors if the integer is negative since PETSc calls to BLAS/LAPACK never need to cast negative integer inputs


## See Also
 `PetscBLASInt`, `PetscMPIInt`, `PetscInt`, `PetscMPIIntCast()`, `PetscIntCast()`, `PetscCountCast()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/include/petscsys.h.html#PetscBLASIntCast">include/petscsys.h</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex50.c.html">src/ts/tutorials/ex50.c.html</A><BR>


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