Consrtaining Variables

*To*: mathgroup at smc.vnet.net*Subject*: [mg26508] Consrtaining Variables*From*: Jeff Hersh <frumple*NOSPAM* at home.com>*Date*: Sat, 30 Dec 2000 01:55:20 -0500 (EST)*Sender*: owner-wri-mathgroup at wolfram.com

I am working on a package where I need to constrain the domain of some variables to the non-negative integers. In particular I would like to be able for Mathematica to recognize that Abs[a-x] = x-a when x>=a where the Abs term is in both the limits and kernal of a Sum. Thanks. Jeff -- Jeffrey Hersh,PhD Remove the *NOSPAM* to reply. <insert amusing quote here>