# VecSetSizes
Sets the local and global sizes, and checks to determine compatibility 
## Synopsis
```
#include "petscvec.h"   
PetscErrorCode VecSetSizes(Vec v, PetscInt n, PetscInt N)
```
Collective


## Input Parameters

- ***v -*** the vector
- ***n -*** the local size (or `PETSC_DECIDE` to have it set)
- ***N -*** the global size (or `PETSC_DETERMINE` to have it set)





## Notes
N cannot be `PETSC_DETERMINE` if n is `PETSC_DECIDE`

If one processor calls this with N of `PETSC_DETERMINE` then all processors must, otherwise the program will hang.


## See Also
 [](chapter_vectors), `Vec`, `VecGetSize()`, `PetscSplitOwnership()`

## Level
intermediate

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

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/utils/tagger/tutorials/ex1.c.html">src/vec/vec/utils/tagger/tutorials/ex1.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/tutorials/ex1.c.html">src/vec/vec/tutorials/ex1.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/tutorials/ex10.c.html">src/vec/vec/tutorials/ex10.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/tutorials/ex11.c.html">src/vec/vec/tutorials/ex11.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/tutorials/ex11f.F90.html">src/vec/vec/tutorials/ex11f.F90.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/tutorials/ex11f90.F90.html">src/vec/vec/tutorials/ex11f90.F90.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/tutorials/ex12.c.html">src/vec/vec/tutorials/ex12.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/tutorials/ex12f.F90.html">src/vec/vec/tutorials/ex12f.F90.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/tutorials/ex13.c.html">src/vec/vec/tutorials/ex13.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/tutorials/ex15.c.html">src/vec/vec/tutorials/ex15.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/vec/tutorials/ex16.c.html">src/vec/vec/tutorials/ex16.c.html</A><BR>


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


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