Re: DiscretePlot

*To*: mathgroup at smc.vnet.net*Subject*: [mg110372] Re: DiscretePlot*From*: "Ingolf Dahl" <ingolf.dahl at telia.com>*Date*: Wed, 16 Jun 2010 05:35:50 -0400 (EDT)

I was about to answer in the following way, as I have done before: "Is there any serious Mathematica user in this forum, which has not stumbled on this problem one or several times, when DiscretePlot, or some other function, tries to evaluate a numeric function symbolically first, before inserting the numbers? Sometimes it would be nice to have an option, SymbolicEvaluation->False, which could be set for DiscretePlot in these cases. It is not always so convenient to have to define an extra function just to take care of this. I think there is a whole group of commands acting similarly to DiscretePlot." But then I tested with all the suggested commands in Mathematica 7.0.1.0 (Windows 7, 64 bit), and I did not obtain any error messages at all. Ingolf Dahl Sweden > -----Original Message----- > From: Andrzej Kozlowski [mailto:akoz at mimuw.edu.pl] > Sent: den 15 juni 2010 08:27 > To: mathgroup at smc.vnet.net > Subject: [mg110348] DiscretePlot > > I am somewhat puzzled by the following behaviour of DiscretePlot > > fff = Compile[{x}, x^2]; > > This works fine: > > DiscretePlot[fff[x], {x, 1, 10, 0.1}, Joined -> True] > > This also works, but produces an error message: > > DiscretePlot[{fff[x]},{x,1,10,0.1},Joined->True] > CompiledFunction::cfsa: Argument x at position 1 should be a machine- > size real number. >> > > This becomes a (slight) problem when plotting several functions. Using > ListLinePlot avoids it: > > ListLinePlot[{Table[fff[x], {x, 1, 10, 0.1}]}, Joined -> True, > Filling -> Bottom] > > Andrzej Kozlowski=