Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!weretis.net!feeder1.news.weretis.net!feeder.erje.net!eternal-september.org!feeder.eternal-september.org!.POSTED!not-for-mail From: Joe Riel Newsgroups: comp.soft-sys.math.maple Subject: Re: Difficulty with simplifying an expression Date: Thu, 22 Sep 2011 14:11:56 -0700 Organization: A noiseless patient Spider Lines: 33 Message-ID: <87k4902sf7.fsf@san.rr.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Injection-Info: mx04.eternal-september.org; posting-host="7daQ3AF9ALJlnU9jGWSG5Q"; logging-data="20410"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+ssgnF8bkLqy/GcQuM7DgQ" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.3 (gnu/linux) Cancel-Lock: sha1:Zw8TacMnruJIEF7LQpl8gg32t+c= sha1:2/unIR/Fy9nQt5IUE/DKJ8DPDZw= Xref: x330-a1.tempe.blueboxinc.net comp.soft-sys.math.maple:244 rouben@shadow.(none) (Rouben Rostamian) writes: > I have tried this in Maple versions 11 through 14. > Maple refuses to do an obvious simplification. > Here are the details. > > Consider the expression "u" produced by: > > with(Statistics): > X:=RandomVariable(Normal(mu,sigma)); > u := AbsoluteDeviation(X,t); > > The expression u consists of a sum of three terms and nops(u) > correctly gives 3. Two of the terms are of the form > "exp(-A) * B * exp(A)" (for some A and B) which should simplify > to B. Doing "simplify(u)" or "simplify(expand(u))" does not > help. > > The only way I could simplify u was by taking it apart, > simplifying each term, then putting it back together, as in: > > v := expand(u); > simplify(op(1,v)) + simplify(op(2,v)) + simplify(op(3,v)); > > Is there a reason why Maple refuses to simplify the original u? I cannot answer that, but a simpler way to do what you want is to use the map command: map(simplify, v); -- Joe Riel