PETSc version 3.15.5
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 Parameter
|  | is1 | - index set to be extended | 
|  | is2 | - index values to be added | 
Output Parameter
|  | is3 | - the sum; this can not be is1 or 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.
See Also
 ISDestroy(), ISView(), ISDifference(), ISExpand()
Level
intermediate
Location
src/vec/is/is/utils/isdiff.c
Index of all IS routines
Table of Contents for all manual pages
Index of all manual pages