Mathematica Graphics

*To*: mathgroup at smc.vnet.net*Subject*: [mg8846] Mathematica Graphics*From*: David Djajaputra <dd4b at virginia.edu>*Date*: Mon, 29 Sep 1997 02:40:18 -0400*Organization*: University of Virginia*Sender*: owner-wri-mathgroup at wolfram.com

Could anyone tell me how to make Mathematica plot the following function smoothly? Wbar[q_,w_]:=w/(4 Sin[q/2]); Chi[q_,w_]:= EllipticF[Pi/2 - ArcSin[Wbar[q,w]], 1/(1-Wbar[q,w]^2)] / Sqrt[1-Wbar[q,w]^2]; ChiPlot[q_,w_]:= If[(w>2 Sin[q])&&(w < 4 Sin[q/2]), Chi[q,w]/(2 Pi Sin[q/2]),0]; Plot[{ChiPlot[0.025,w]},{w,0.04999,0.050},PlotPoints->200, PlotRange->{19.998,20.003}] If I run the last Plot command, Mathematica always complains about ChiPlot[w] not being a machine-size real number at some points, and then it only plots several disconnected lines. I realize the function is rather `dangerous' but analytically I expect it to behave normally inside the region that I use above, except perhaps at the boundaries. Anyway, if Mathematica can get the separate lines, why can't it obtain the values for points between the lines also? Much thanks in advance, David Djajaputra