# MatPreallocateEnd
Ends the block of code that will count the number of nonzeros per row in a matrix providing the data that one can use to correctly preallocate the matrix. 
## Synopsis
```
#include <petscmat.h>
PetscErrorCode MatPreallocateEnd(PetscInt *dnz, PetscInt *onz)
```
Collective


## Input Parameters

- ***dnz -*** the array that was be passed to the matrix preallocation routines
- ***onz -*** the other array passed to the matrix preallocation routines





## Notes
This is a macro that handles its own error checking, it does not return an error code.

See Users-Manual: ch_performance for more details.

Do not malloc or free dnz and onz, that is handled internally by these routines


## Developer Notes
This is a MACRO not a function because it closes the { started in MatPreallocateBegin().


## See Also
 `MatPreallocateBegin()`, `MatPreallocateSet()`, `MatPreallocateSymmetricSetBlock()`, `MatPreallocateSetLocal()`,
`MatPreallocateSymmetricSetLocalBlock()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/include/petscmat.h.html#MatPreallocateEnd">include/petscmat.h</A>


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