Re: Mathematica 5 : strange Plot

*To*: mathgroup at smc.vnet.net*Subject*: [mg43975] Re: [mg43945] Mathematica 5 : strange Plot*From*: Andrzej Kozlowski <akoz at mimuw.edu.pl>*Date*: Thu, 16 Oct 2003 04:16:09 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

On Wednesday, October 15, 2003, at 05:59 PM, pacotomi wrote: > Hi, > Plot[ ] gives me a perplexing graphic : > > let : > > f[x_] := If [x < 20, 0, x - 20] > > Then, I try : > > Plot[f[x], {x, 0, 100}] > > curiously, I get a plot with x between 0 and 40 and f(x) between 0 and > 80. The x range is false but the y one is right. > > What's wrong with this simple notebook ? > > Pacotomi > > > You should tell mathemaitca the plot range you want: 1. Plot[f[x], {x, 0, 100}, PlotRange -> All] 2. Plot[f[x], {x, 0, 100}, PlotRange -> {{0, 100}, {0, 80}}] Otherwise Mathematica uses it's own algorithm for choosing the "interesting" plot range, which often produces better looking pictures but is not always what you want. Andrzej Kozlowski Yokohama, Japan http://www.mimuw.edu.pl/~akoz/ http://platon.c.u-tokyo.ac.jp/andrzej/