ASPL Set Operations

ASPL provides symbolic set operators to do operations on your set variables, these operators are called setops and they perform various set operations on your datasets, such as intersection, union, difference, symmetric difference, and partition. The following is a list of the setops: f& fU f\ fD fP d& dU d\ dD dP g& gU g\ gD gP
These set operators are called setadic operators. In an expression, a setadic operator happens to be the leftmost operator mnemonic, and may be followed either by one or more set variables, or by an expression.
The set operator can be niladic, that it can be issued by itself without following it by any arguments, in which case the operator sources its operands from the anonymous groups saved in the answer stack.
In addition, ASPL setops can be ticked with predicates to associate the set operations (with the conditional such-as) at the elements attribute level. ASPL setops can also be suffixed with a preprogrammed quotient relation. More interesting set operations can be performed with shallow set operators and fuzzy set operators, they are covered in their own chapters. The following chapter consists of pages describing ASPL setops.

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