Display selected region of a table of polygons
- To: mathgroup at smc.vnet.net
- Subject: [mg107895] Display selected region of a table of polygons
- From: "Dominic" <miliotodc at rtconline.com>
- Date: Tue, 2 Mar 2010 03:37:04 -0500 (EST)
Hello,
Can someone tell me if there is a way to display a selected angular
region of a table of polygons representing a surface? I don't think
RegionFunction, Exclusion, or RegionPlot can do this. Not sure though.
For example, the code below creates a table of polygons representing
Im[Sin[z]] in a circle of radius two. Suppose now I only want to
display the surface between angles startT=1.2 and endT=2.5
(radians). I don't know how to do this other than re-acquire the data
between those two angles but the actual application I'm writing already
has the data conveniently acquired in the 2pi region.
Thanks guys,
Dominic
f[z_] := Sin[z];
mypTable = Table[{r*Cos[t], r*Sin[t], Im[f[r*Exp[I*t]]]},
{r, 0.001, 2, 0.1}, {t, 0, 2*Pi, Pi/10}];
tval = Length[mypTable]
rval = Length[mypTable[[1]]]
myPolygons = Table[Polygon[{mypTable[[i, j]], mypTable[[i + 1, j]],
mypTable[[i + 1, j + 1]], mypTable[[i, j + 1]]}],
{j, 1, rval - 1}, {i, 1, tval - 1}];
pic1 = Show[Graphics3D[myPolygons]]