ISGlobalToLocalMappingApply

Provides the local numbering for a list of integers specified with a global numbering.

Synopsis

#include "petscsys.h" 
#include "petscis.h"  
int ISGlobalToLocalMappingApply(ISLocalToGlobalMapping mapping,ISGlobalToLocalMappingType type,
                                  int n,const int idx[],int *nout,int idxout[])

Not collective

Input Parameters

	mapping	- mapping between local and global numbering
	type	- IS_GTOLM_MASK - replaces global indices with no local value with -1 IS_GTOLM_DROP - drops the indices with no local value from the output list
	n	- number of global indices to map
	idx	- global indices to map

Output Parameters

	nout	- number of indices in output array (if type == IS_GTOLM_MASK then nout = n)
	idxout	- local index of each global index, one must pass in an array long enough to hold all the indices. You can call ISGlobalToLocalMappingApply() with idxout == PETSC_NULL to determine the required length (returned in nout) and then allocate the required space and call ISGlobalToLocalMappingApply() a second time to set the values.

Notes

Either nout or idxout may be PETSC_NULL. idx and idxout may be identical.

This is not scalable in memory usage. Each processor requires O(Nglobal) size array to compute these.

Examples