(50g) Removing Objects From Lists Quickly

[John Keith]

In addition to the terminological confusion, there seem to be several differences (pun intended) in the way these functions are implemented. In Mathematica, both Complement and Union return sorted lists; GoferLists and the Prime return lists containing elements in the original order that they occurred in the input lists.

Also, I have noticed that INTERSECT on the Prime does return lists with some duplicate elements if the first input list contains duplicates. Therefor I am removing the final LDDUP command in my intersection program in post #3. The program will be faster, and users can always execute LDDUP themselves afterwards if they wish.