Computes the difference between two index sets.
PetscErrorCode ISDifference(IS is1,IS is2,IS *isout)
Collective on IS
|is1 ||- first index, to have items removed from it
|is2 ||- index values to be removed
isout -is1 - is2
Negative values are removed from the lists. is2 may have values
that are not in is1. This requires O(imax-imin) memory and O(imax-imin)
work, where imin and imax are the bounds on the indices in is1.
If is2 is NULL, the result is the same as for an empty IS, i.e., a duplicate of is1.
ISDestroy(), ISView(), ISSum(), ISExpand()
Index of all IS routines
Table of Contents for all manual pages
Index of all manual pages