:orphan:
# ISLocalToGlobalMappingGetBlockInfo
Gets the neighbor information for each processor and each index shared by more than one processor 
## Synopsis
```
#include "petscis.h"  
PetscErrorCode ISLocalToGlobalMappingGetBlockInfo(ISLocalToGlobalMapping mapping, PetscInt *nproc, PetscInt *procs[], PetscInt *numprocs[], PetscInt **indices[])
```
Collective


## Input Parameter

- ***mapping -*** the mapping from local to global indexing



## Output Parameters

- ***nproc -*** number of processors that are connected to this one
- ***proc -*** neighboring processors
- ***numproc -*** number of indices for each subdomain (processor)
- ***indices -*** indices of nodes (in local numbering) shared with neighbors (sorted by global numbering)





## Fortran Usage
```none
        PetscInt indices[nproc][numprocmax],ierr)
        ISLocalToGlobalMpngGetInfoSize(ISLocalToGlobalMapping,PetscInt nproc,PetscInt numprocmax,ierr) followed by
        ISLocalToGlobalMappingGetInfo(ISLocalToGlobalMapping,PetscInt nproc, PetscInt procs[nproc],PetscInt numprocs[nproc],
```



## Fortran Note
There is no `ISLocalToGlobalMappingRestoreInfo()` in Fortran. You must make sure that `procs`[], `numprocs`[] and
`indices`[][] are large enough arrays, either by allocating them dynamically or defining static ones large enough.


## See Also
 [](sec_scatter), `ISLocalToGlobalMappingDestroy()`, `ISLocalToGlobalMappingCreateIS()`, `ISLocalToGlobalMappingCreate()`,
`ISLocalToGlobalMappingRestoreInfo()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/vec/is/utils/isltog.c.html#ISLocalToGlobalMappingGetBlockInfo">src/vec/is/utils/isltog.c</A>


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


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