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Topic: Need a functional process for this.
Replies: 5   Last Post: Mar 31, 2005 1:50 AM

 Messages: [ Previous | Next ]
 Steve Gray Posts: 129 Registered: 12/4/04
Need a functional process for this.
Posted: Mar 30, 2005 3:53 AM

I have two lists, aa and bb. aa has the general form {2,5,7,9,11,...}
(or{{2},{5},{7},{9},{11},}}), and bb has the general form {{6,4},{9,2},{5,6},{3,8},}. If either
the first or second element in any sublist (pair of integers) of bb matches any element in aa, I
want to delete that sublist from bb. In the above example, neither member of {6,4} or {3,8} belongs
to aa, while at least one element of {9,2} and {5,6} belongs to aa, so bb becomes {{6,4},{3,8}}. If
aa had only one element, for example 7, I could do bb=Delete[bb,Position[bb,{x_,7}|{7,y_}]], but I
don't know how to do it for several values instead of just "7" without using a procedural loop.
What is a good functional way to do this?
Thank you for any tips.

Steve Gray

Date Subject Author
3/30/05 Steve Gray
3/30/05 Curt Fischer
3/31/05 Curt Fischer
3/31/05 dh
3/31/05 Brian Higgins
3/31/05 Ray Koopman