ISSum#
Computes the sum (union) of two index sets.
Synopsis#
#include "petscis.h"  
PetscErrorCode ISSum(IS is1, IS is2, IS *is3)
Only sequential version (at the moment)
Input Parameters#
- is1 - index set to be extended 
- is2 - index values to be added 
Output Parameter#
- is3 - the sum; this can not be - is1or- is2
Notes#
If n1 and n2 are the sizes of the sets, this takes O(n1+n2) time;
Both index sets need to be sorted on input.
The sum is computed separately on each MPI rank
See Also#
Low-level Vector Communication, IS, ISDestroy(), ISView(), ISDifference(), ISExpand()
Level#
intermediate
Location#
Index of all IS routines
Table of Contents for all manual pages
Index of all manual pages