Re: Re: confused about asserting variable is element of
- To: mathgroup at smc.vnet.net
- Subject: [mg103204] Re: [mg103141] Re: confused about asserting variable is element of
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Thu, 10 Sep 2009 07:22:42 -0400 (EDT)
- Reply-to: hanlonr at cox.net
It wouldn't have any effect. It just evaluates to False Element[I, Reals] False Simplify[Re[I], Element[I, Reals]] Simplify::fas: Warning: One or more assumptions evaluated to False. >> 0 Simplify[Im[I], Element[I, Reals]] Simplify::fas: Warning: One or more assumptions evaluated to False. >> 1 Bob Hanlon ---- AES <siegman at stanford.edu> wrote: ============= In article <h859vn$q48$1 at smc.vnet.net>, Leonid Shifrin <lshifr at gmail.com> wrote: > When you enter Element[a, Reals], this by itself does nothing. It does not, > in particular, change any global property of symbol <a>. > > However, this expression can be used in > commands like Simplify, FullSimplify, etc., to give them the information > that <a> should be considered real (in that particular computation): So, could one ever write Assumptions -> Element[I, Reals] in any of those commands?