Hello everybody !!! I recently had to write two very easy lines of python, and I wondered if there was ( there is ) a better way to write them. The problem is easy : I have a list A, a list B whose elements all belong to A, and I want to return A-B.
I wrote [v for v in A if v not in B] which may be the worst option. I thought about list(Set(A)-Set(B)), or about first sorting both lists (nlog n) then taking the difference in linear time. Well, perhaps the overhead due to sorting or to coercion to Sets is already too much for this application ( the sets in questions where vertices in a Graph, and the other parts of the function in which they are used is already quite long ), but, well, I wondered... :-) Thanksssssss ! :-) Nathann -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
