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how to calculate difference and intersection of two sets?

2 posts · 5443 views

Lebesgue

#1 Thu Jun 07, 2012 9:15 pm

Hi,
How to calculate the difference and intersection of two sets,which are lists ?
thx.

edgar-rft

#2 Sat Jun 09, 2012 9:54 am

Re: how to calculate difference and intersection of two sets

From inside Emacs, first evaluate:

(require 'cl)

You need to evaluate (require 'cl), because the Emacs "set-difference" and "intersection" functions are defined in "cl-seq.el", that is no standard part of Emacs, then try:

C-h f set-difference
C-h f intersection

and click on the source links in the *Help* buffer. The source links work of course only if the Emacs sources are installed.