how to draw manifold?

Hi:

Here's an example stolen out of the scatterplot3d package vignette (p. 9):

library(scatterplot3d)
z<- seq(-10, 10, 0.01)
x<- cos(z)
y<- sin(z)
scatterplot3d(x, y, z, highlight.3d = TRUE, col.axis = 'blue',
               col.grid = 'lightblue', main = 'Helix', pch = 20)

HTH,
Dennis

On Sat, Nov 20, 2010 at 8:29 AM, Carl Witthoft<carl at witthoft.com>  wrote:

Hi,
I need some help either in how to configure variables for wireframe(), or
some suggestions as to other graphics commands to use for plotting a 2-D
manifold in 3-D space.

Here is an example I tried (in the hopes that it would plot a helical line)
:

xsp<-matrix(c(cos(seq(0,80)/5)),9,9)
ysp<-matrix(c(sin(seq(0,80)/5)),9,9)
zsp<-matrix(c((seq(0,80)/20)),9,9)
wireframe(zsp~xsp*ysp)

The resulting plot looks vaguely like a helix, but not right.  And if I
change my variables' dimensions to c(3,27) it looks "better," but if the
dims are c(1,81), nothing gets plotted.

So: is there a way to control which points are connected by lines in
wireframe()?  Or is there a more appropriate way to provide a plotting
program with sets of coordinates in 3-space?

My primary goal is to be able to plot surfaces, not just a line as in my
sample code.  For example, I might expand the data above to represent points
on a 'ribbon' helix.

Thanks for yr. help -- feel free to point me to help files for existing
packages or plotting routines.

Carl