NAME set_subtract - place difference of two sets in a third SYNOPSIS subroutine set_subtract (set1, set2, destination) pointer set1, set2, destination DESCRIPTION 'Set_subtract' performs the set subtraction operation, i.e. places in the set 'destination' those elements of 'set1' that are not in 'set2'. For proper operation, all three sets should be the same size. All set manipulation routines make use of dynamic storage, which must be initialized before use. See 'dsinit' for further information. Note that all set manipulation routines have long names. To avoid unique name conflicts with other routines, any Ratfor program using the set routines should include the following statement: include "=src=/lcl/lib/swtmlb.u/swtmlb_link.r.i" IMPLEMENTATION Since sets are represented as bit vectors, the subtraction operation is performed by logically 'and'ing the elements of the first set with the negation of the elements of the second set. BUGS Should work with sets of differing sizes. SEE ALSO other set routines ('set_?*') (4)