error messages in Mathematica 9
- To: mathgroup at smc.vnet.net
- Subject: [mg128947] error messages in Mathematica 9
- From: Ã. Holen <o.h.holen at bio.uio.no>
- Date: Wed, 5 Dec 2012 03:12:58 -0500 (EST)
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I find that code that worked well in Mathematica 8 often produces error messages in Mathematica 9, although graphs are still produced correctly. The following code is a constructed example that illustrates the issue I'm struggling with:
f[x_] := Module[{y}, y /. FindRoot[x - y, {y, 0}]];
RegionPlot[ f[x] > 0, {x, -1, 1}, {b, -1, 1}]
Any suggestions about what the error is?
Typical error messages are:
FindRoot::nlnum: The function value {0. +Region`Private`RegionVar[1.]} is not a list of numbers with dimensions {1} at {y$897} = {0.}. >>
ReplaceAll::reps: {FindRoot[Region`Private`RegionVar[1]-y$897,{y$897,0}]} is neither a list of replacement rules nor a valid dispatch table, and so cannot be used for replacing. >>