Re: Define a function
- To: mathgroup at smc.vnet.net
- Subject: [mg34617] Re: Define a function
- From: "Steve Durbin" <steved at vale.demon.co.uk>
- Date: Wed, 29 May 2002 02:47:02 -0400 (EDT)
- References: <acshar$ke2$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
"Michael Popp" <popp.michael at gmx.at> wrote in message news:acshar$ke2$1 at smc.vnet.net... > Hello > > I want to define a function in Mathematica. But just f[x_]:=... does not > work, because I have to define different functions for different ranges of > the variable x. > For example: > > x < 10: f(x) = 0 > 10 < x < 20: f(x) = x > 20 < x: f(x) = x/2 > > How to do this? Michael, See the Mathematica help under "Domain" (section 2.3.5). Here's the specific solution to your example - the /; gives the domain for that part of the function. f[x_] := 0 /; x < 10 f[x_] := x /; 10 <= x <= 20 f[x_] := x/2 /; x > 20 Cheers, -- Steve Durbin | Look! Minimalism comes to ASCII art! | .