efficient binary relations?
 Christian Lindig
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Date:   (:) 
From:  Christian Lindig <lindig@c...> 
Subject:  efficient binary relations? 
I am looking for an efficient representation of binary relations in OCaml. I have used bitvectors in the past but would like to use a more highlevel and less imperative data structure. The most important operation is the following. For a binary relation R over \X x \Y compute for a set X the set X' = { y  (x,y) in R for all x in X}. In other words, X' is the set of y that are common to all x in X. Likewise, Y' must be computed. This operation requires to compute the intersection of sets and was the main reason I chose bitvectors. If you know about a suitable data structure I would glad to hear about it.  Christian  http://www.st.cs.unisb.de/~lindig/