Re: Plotting complex functions

*To*: mathgroup at smc.vnet.net*Subject*: [mg24163] Re: Plotting complex functions*From*: piovere at pdq.net (rob)*Date*: Wed, 28 Jun 2000 22:50:45 -0400 (EDT)*References*: <8ihvf8$lgj@smc.vnet.net> <8ikbp4$qaa@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Say, I tried you example but for some reason I get the err msg that ParametricPlot does not evaluate to a pair of real numbers. Should this work on my version 4.0? Thanks, Rob On 19 Jun 2000 01:40:52 -0400, "Kevin J. McCann" <kevinmccann at Home.com> wrote: >Matthijs , > >In order to plot, the function has to produce numbers. Your example below >has two undetermined integration constants; so, the result will not produce >a number. Try the example below. I picked the IC's so that the result would >be complex. > >Paste these into a NB > >f=y/.DSolve[{y''[t] + y'[t] + y[t] == 0,y[0]==I,y'[0]==1}, y, t] > >ParametricPlot[{Re[f[x]], Im[f[x]]}, {x, 0, 10}, > Epilog -> {RGBColor[1, 0, 0], AbsolutePointSize[5], >Point[{Re[f[0.]], Im[f[0.]]}]}]; > >Cheers, > >Kevin > >"Matthijs Sypkens Smit" <matthijs at helena.tux.nu> wrote in message >news:8ihvf8$lgj at smc.vnet.net... >> Hi, >> >> How do I make a plot of a complex-valued function, such as y after >> DSolve[y''[t] + y'[t] + y[t] == 0, y, t] >> >> I've tried a ParametricPlot with Re[y[t] and Im[y[t], but either that >> doesn't work or I'm doing it wrong. Any pointers or an example? >> >> -- >> Matthijs >> > Please use robpeterson at iname.com for email. http://freeweb.pdq.net/piovere <AHREF="http://freeweb.pdq.net/piovere/";>(added for the AOL-challenged)