:orphan:
# ISGlobalToLocalMappingApplyIS
Creates from an `IS` in the global numbering a new index set using the local numbering defined in an `ISLocalToGlobalMapping` context. 
## Synopsis
```
#include "petscis.h"  
PetscErrorCode ISGlobalToLocalMappingApplyIS(ISLocalToGlobalMapping mapping, ISGlobalToLocalMappingMode type, IS is, IS *newis)
```
Not Collective


## Input Parameters

- ***mapping -*** mapping between local and global numbering
- ***type -*** `IS_GTOLM_MASK` - maps global indices with no local value to -1 in the output list (i.e., mask them)
`IS_GTOLM_DROP` - drops the indices with no local value from the output list
- ***is -*** index set in global numbering



## Output Parameter

- ***newis -*** index set in local numbering





## Note
The output `IS` will be sequential, as it encodes a purely local operation


## See Also
 [](sec_scatter), `ISGlobalToLocalMapping`, `ISGlobalToLocalMappingApply()`, `ISLocalToGlobalMappingCreate()`,
`ISLocalToGlobalMappingDestroy()`

## Level
advanced

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


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