Re: Plotting 3D discrete points

[Michael Goffioul]

On Mon, May 19, 2008 at 7:43 AM, Oren Spector <address@hidden> wrote:
> Hello Octave users,
>
> I am new to this mailing list, so forgive me if a similar question was
> asked before. (By the way, is there a search ability in the mailing
> list archives? I couldn't find one)

http://www.nabble.com

> I have a set of points in 3D space in an Nx3 matrix, which I call
> "bd". This set of points is a discrete representation of some region
> boundary in 3D space.
>
> I use plot3 in order to visualize this set. If I use plot3( bd( :, 1
> ), bd( :, 2 ), bd( :, 3 ) ) Octave connects the points in the order in
> which they appear in the matrix. But, I want to plot the set as
> discete points. I found that by using plot3( bd( :, 1 ), bd( :, 2 ),
> bd( :, 3 ), '+' ) I get a discrete plot, but each point appears as a
> '+' sign, which makes the plot cumbersome. How can I plot the set as
> discrete point, where each point appears as a dot?

plot3(..., '.')

> Since the boundary I'm plotting is a closed surface I wish to use
> different colors to ease its viewing. I want something similar to a
> topographic map, in which different values in the Z-axis are colored
> differently. Is there a simple method of doing that in Octave?

See scatter3.

Michael.