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minus

Function minus


Calling Sequence  a minus b
minus(a,b)
Parameters
NameTypeDescription

a a set 
b a set 
Return Type  set
Synopsis Computes the set difference of two sets; that is a set consisting of all elements in a but not in b. The value intersect() is understood to be the entire universe, and hence subtracting intersect() will return the empty set and subtracting from intersect() is not allowed.
Examples
> {1,2,3} minus {2,3,4};
{1}
> {1,2,3} minus {};
{1,2,3}
> {1,2,3} minus intersect();
{}
See also intersect,   member,   subset,   union