Re: Cannot plot this functions

*To*: mathgroup at smc.vnet.net*Subject*: [mg53863] Re: Cannot plot this functions*From*: D Herring <dherring at at.uiuc.dot.edu>*Date*: Tue, 1 Feb 2005 04:08:13 -0500 (EST)*References*: <ctfv5b$pe2$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

> I need to plot the negative derivative of this function with respect > to Ï?. Whne I use plot it gives me the error: > > function is not a machine - size real number at Ï? =1.8622242690864824`*^-7 Sometimes, simply wrapping your expression in an Evaluate[] will eliminate this error. I've had several troublesome cases where Plot[EXPRESSION, {t,0,10}] gave "function is not a ... at t=4..." while Plot[Evaluate[EXPRESSION], {t,0,10}] works just fine. They hint about this in the documentation, but its still easy to miss. Hope that helps, Daniel