Re: HELP: Plot[]ing composite functions
- To: mathgroup at smc.vnet.net
- Subject: [mg16007] Re: HELP: Plot[]ing composite functions
- From: Paul Abbott <paul at physics.uwa.edu.au>
- Date: Sat, 20 Feb 1999 02:52:01 -0500
- Organization: University of Western Australia
- References: <7ag4kt$b0q@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Alexander Sirotkin wrote:
> Simple question - after definition of a functions
> which looks like this "H[w] == Log[10, 1 + Exp[I2Pi w]]"
> I try to Plot[] it and get the "... not machine size real
> number at ..." error.
Because you are trying to plot a complex-valued function. Try
H[w_] = Log[10, 1 + E^(I*2*Pi*w)];
Plot[Abs[H[w]], {w, 0, 4}];
or, more efficiently,
Plot[Evaluate[Abs[H[w]]], {w, 0, 4}];
Cheers,
Paul
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Paul Abbott Phone: +61-8-9380-2734
Department of Physics Fax: +61-8-9380-1014
The University of Western Australia
Nedlands WA 6907 mailto:paul at physics.uwa.edu.au
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God IS a weakly left-handed dice player
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