non integer exponents in ContourPlot[]?

*To*: mathgroup at smc.vnet.net*Subject*: [mg35209] non integer exponents in ContourPlot[]?*From*: "1.156" <rob at piovere.com>*Date*: Tue, 2 Jul 2002 02:12:11 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

Mathematica wizards all: The following code runs fine, note the (apparent) floating point form of the exponents. a=-5.75;b=2;d=1.1; ContourPlot[a*((x^2.0 + y^2.0)^0.5 + b*y^2.0), {x, -d, d}, {y, -d, d}, ContourShading -> False, Contours -> {-6, -3, -1}, PlotPoints -> 30]; But, if I make any of the 2.0 exponents say, 2.1, I get big error messages like ContourGraphics::ctpnt: The contour is attempting to traverse a cell in which some of the points have not evaluated to numbers, and it will be dropped. However, it works fine if I change the 0.5 exponent to say, 0.55. Can anyone give me a hint of what's going on here? I'd sure like to be able to play with these exponents to fit some data. Thanks, Rob

**Follow-Ups**:**Re: non integer exponents in ContourPlot[]?***From:*Tomas Garza <tgarza01@prodigy.net.mx>