Union question

*To*: mathgroup at smc.vnet.net*Subject*: [mg13889] Union question*From*: Garrett Andrew Storaska <gas2y at node4.unix.virginia.edu>*Date*: Sun, 6 Sep 1998 02:55:27 -0400*Organization*: University of Virginia*Sender*: owner-wri-mathgroup at wolfram.com

I'm trying to take a very long list of real numbers and use the Union function on it to remove duplicates. The problem is that the real numbers that I consider to be the same, differ after their 12th decimal place. I have tried without sucess to use N and SetAccuracy functions on each element of the list Before using the Union Function, but to no Avail. Is there any quick way to take a long list, and remove duplicate elements by comparing only the first n significant digets of each element. Thanks, Garrett Storaska