Set theory (operators)

[DrD]

Han, thanks for responding. I tried and learned from your examples, however on emu the form:

union( {1,2}, {1,2,3} ) did not work for me; {1,2} union {1,2,3} worked great!

intersect( {1,2}, {1,2,3} ) worked using both methods.

So a couple of things:

I could find no reference to help on-calc or user guide, for the 'union' function. The 'intersect' function does have help support, but does not reveal an example like you've given: {1,2} intersect {1,2,3}.

The main point of my posting, however, was not about the functions. It is about set notation operators that invoke the operation: (U or ∩). There have been times when I would have liked to have been able to use: {1,2} U {1,2,3}, instead of the longer form: {1,2} union {1,2,3}, for SET operations (example).

Help for 'intersect' while available, worked as expected on-calc, but one would probably search the user guide for "intersection," and quickly discover a lot of hits focused mainly on plotting, or at least within a graphical context, not set theory.

Usually, when I wonder about such things, Joe Horn shows up with some clever way I never thought of, to solve sometimes more than I was even questioning, and so I "put it out there" to see if he, or someone, had discovered trickery absent from help files!

I appreciate your taking the time to shed additional light on this!

-Dale-