Re: global assumptions?? How far can I go?

*To*: mathgroup at smc.vnet.net*Subject*: [mg53338] Re: global assumptions?? How far can I go?*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Thu, 6 Jan 2005 22:00:39 -0500 (EST)*Reply-to*: hanlonr at cox.net*Sender*: owner-wri-mathgroup at wolfram.com

Options[Integrate] {Assumptions :> $Assumptions, GenerateConditions -> Automatic, PrincipalValue -> False} The conditions are useful for assisting in verifying that what led up to the integration is correct. If the conditions don't make sense, then there was most likely an error. Once you have reviewed the conditions and want them subsequently ignored, turn them off. Integrate[1/x^2,{x,1,t}, GenerateConditions->False] (t - 1)/t or "globally" SetOptions[Integrate,GenerateConditions->False]; Integrate[1/x^2,{x,1,t}] (t - 1)/t Bob Hanlon > > From: Ron Griffin <ron-griffin at tamu.edu> To: mathgroup at smc.vnet.net > Date: 2005/01/06 Thu AM 02:52:11 EST > To: mathgroup at smc.vnet.net > Subject: [mg53338] global assumptions?? How far can I go? > > I'm an economist whose accustomed to emphasizing the first orthant in a > noncomplex world (positive, real prices; positive, real, quantities) so > I really get flustered when Mathematica "pollutes" my output with "using inverse > function" warnings and imaginary solutions. > > Now I've "upgraded" to 5.1 from 4.2 and I find, as I expected from my > experience during previous upgrades, that Mathematica is even more anal than it > was before. Hence, programs which ran well under 4.2 now are less > functional because Mathematica is increasingly careful. > > So, how global can I go in telling Mathematica to assume that all the variables > I create are real?? Must I list an assumption for each variable or each > command?? Jees, now it won't even integrate 1/x^2 from 1 to t without > dumping a bunch of worries on me. > > ron > >