Re: Combining two paramteric plots into one.
- To: mathgroup at smc.vnet.net
- Subject: [mg49119] Re: Combining two paramteric plots into one.
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Fri, 2 Jul 2004 02:01:18 -0400 (EDT)
- Organization: Universitaet Leipzig
- References: <cc0luf$kp5$1@smc.vnet.net>
- Reply-to: kuska at informatik.uni-leipzig.de
- Sender: owner-wri-mathgroup at wolfram.com
Hi, what may the option DisplayFunction->Identity do ? Supress the output from a generated graphics ?? ellipsePlot[{xc_, yc_, w_, h_, a_}, n_] := ParametricPlot[ {ellipsePoint[{xc, yc, w, h, a}, 2\[Pi] t/n][[1]], ellipsePoint[{xc, yc, w, h, a}, 2\[Pi] t/n][[2]]}, {t, 0, n}, AspectRatio -> Automatic,DisplayFunction->Identity] ellipsePlotTwo[{xc1_, yc1_, w1_, h1_, a1_}, {xc2_, yc2_, w2_, h2_, a2_}] := Show[ ellipsePlot[{xc1, yc1, w1, h1, a1}], ellipsePlot[{xc2, yc2, w2, h2, a2}],DisplayFunction->$DisplayFunction] Regards Jens Bob Harris wrote: > > Howdy, > > I'm trying to plot two ellipses together on one plot. I have accomplished > this, except that mathematica plots three figures-- ellipse 1, then ellipse > 2, then the combination of the two. I want to avoid the first two figures. > > Here's what I am doing. > > ellipsePoint[{xc_, yc_, w_, h_, a_}, t_] := > {((w Cos[a] Cos[t] - h Sin[a] Sin[t]) + xc)/2, > ((w Sin[a] Cos[t] + h Cos[a] Sin[t]) + yc)/2} > > ellipsePlot[{xc_, yc_, w_, h_, a_}] := > ellipsePlot[{xc, yc, w, h, a}, 20] > > ellipsePlot[{xc_, yc_, w_, h_, a_}, n_] := > ParametricPlot[ > {ellipsePoint[{xc, yc, w, h, a}, 2\[Pi] t/n][[1]], > ellipsePoint[{xc, yc, w, h, a}, 2\[Pi] t/n][[2]]}, > {t, 0, n}, > AspectRatio -> Automatic] > > ellipsePlotTwo[{xc1_, yc1_, w1_, h1_, a1_}, > {xc2_, yc2_, w2_, h2_, a2_}] := > Show[ > ellipsePlot[{xc1, yc1, w1, h1, a1}], > ellipsePlot[{xc2, yc2, w2, h2, a2}]] > > Apparently what happens is ParametricPlot[...] always draws a figure so when > I call it inside Show (via ellipsePlot[...]), I get a figure drawn that I > don't want to draw yet. How can I call ParametricPlot and just get the > resulting graphical object without it drawing it? > > I have similar problems with other combinations with ellipsePlot. For > example, using ListPlot to try to add a list of points on the figure (i.e. > Show[ellipsePlot[...], ListPlot[...]]) I get three figures instead of just > the one I want. > > Thanks, > Bob H