Re: coloring eveerything outside a circle

*To*: mathgroup at smc.vnet.net*Subject*: [mg31818] Re: coloring eveerything outside a circle*From*: "Ersek, Ted R" <ErsekTR at navair.navy.mil>*Date*: Wed, 5 Dec 2001 06:51:40 -0500 (EST)*Sender*: owner-wri-mathgroup at wolfram.com

mipam wrote: > > Is it possible with Mathematica to draw a circle, or > parametricplot and paint everything white outside that > circle, or closed curve (which is given by parametricplot)? > Or is it possible to paint everything white between two > closed curves or circles? > Making something like a black inner tube (whith a white center) is trivial. To do that you show a circle and then a smaller white circle on-top of the first circle. However, it's a little tricky if you want to "see" the graphics behind the center of the inner tube. Below I show how that can be done. -------------------------- Block[{$DisplayFunction=Identity}, gr1=ParametricPlot[ {2*Sin[t], 2*Cos[t]+2}, {t, 0, 2 Pi} ]; gr2=ParametricPlot[ {Sin[t]+1/2, Cos[t]+2}, {t, 0, 2 Pi} ] ]; pnts=Join[ Part[gr1,1,1,1,1], Part[gr2,1,1,1,1] ]; gr3=Graphics[ { Hue[1], Polygon[pnts] } ]; gr4=Graphics[ { Hue[0.6], Polygon[ {{-2.5,3.75}, {-2.5,3.5}, {3,0.75}, {3,1}} ] }]; Show[{gr4,gr3}, AspectRatio->Automatic]; ------------------ Regards, Ted Ersek Check Mathematica Tips, Tricks at http://www.verbeia.com/mathematica/tips/Tricks.html