# DMNetworkCreateIS
Create an index set object from the global vector of the network 
## Synopsis
```
#include "petscdmnetwork.h"  
PetscErrorCode DMNetworkCreateIS(DM dm, PetscInt numkeys, PetscInt keys[], PetscInt blocksize[], PetscInt nselectedvar[], PetscInt *selectedvar[], IS *is)
```
Collective


## Input Parameters

- ***dm -*** DMNetwork object
- ***numkeys -*** number of keys
- ***keys -*** array of keys that define the components of the variables you wish to extract
- ***blocksize -*** block size of the variables associated to the component
- ***nselectedvar -*** number of variables in each block to select
- ***selectedvar -*** the offset into the block of each variable in each block to select



## Output Parameters

- ***is -*** the index set





## Notes
Use blocksize[i] of -1 to indicate select all the variables of the i-th component, for which nselectvar[i] and selectedvar[i] are ignored. Use NULL, NULL, NULL to indicate for all selected components one wishes to obtain all the values of that component. For example, DMNetworkCreateIS(dm,1,&key,NULL,NULL,NULL,&is) will return an is that extracts all the variables for the 0-th component.


## See Also
 `DMNetworkCreate()`, `ISCreateGeneral()`, `DMNetworkCreateLocalIS()`

## Level
Advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/impls/network/network.c.html#DMNetworkCreateIS">src/dm/impls/network/network.c</A>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/dm/impls/network/network.c)


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