Mathematica 5 : strange Plot

*To*: mathgroup at smc.vnet.net*Subject*: [mg43945] Mathematica 5 : strange Plot*From*: pacotomi at wanadoo.fr (pacotomi)*Date*: Wed, 15 Oct 2003 04:59:21 -0400 (EDT)*Organization*: Wanadoo, l'internet avec France Telecom*Sender*: owner-wri-mathgroup at wolfram.com

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