Thread Subject: Plotting a surface with 'holes'

I have the x-y-z coordinates of a set of points which I'd like to plot
as a 3-D surface. At some coordinates, the points do not exist. The
plotted surface should therefore show gaps or 'holes' in areas where
points are missing. I've tried the 'surf' command but that doesn't
render the desired surface. I found that 'surf' fits a nice smooth
surface over the points while interpolating between the points, hence
filling in those 'holes'.
Is there a another Matlab command or any way in Matlab to get the plot
I'm after ? Thanks a lot for your help.

Ray

"Ray" <rbenbernou@yahoo.com> wrote in message
news:4b1c137e-8df2-4f78-9e96-dc4e922d02df@p6g2000pre.googlegroups.com...
>I have the x-y-z coordinates of a set of points which I'd like to plot
> as a 3-D surface. At some coordinates, the points do not exist. The
> plotted surface should therefore show gaps or 'holes' in areas where
> points are missing. I've tried the 'surf' command but that doesn't
> render the desired surface. I found that 'surf' fits a nice smooth
> surface over the points while interpolating between the points, hence
> filling in those 'holes'.
> Is there a another Matlab command or any way in Matlab to get the plot
> I'm after ? Thanks a lot for your help.
>
> Ray

Put a NaN in your data where you want the hole to be placed.

--
Steve Lord
slord@mathworks.com

Ray:

Hi !
I'm not sure if I can help you, but try with the folowing commands:

X = [1, 3, 5]; Y = [1, 2, 6]; Z = [1, 3, 4]; % Defining 3 points
tcolor = [1 1 1]; % Defining color
patch(X,Y,Z,tcolor); % Graph of the poligon with X Y Z vertexs
grid on; view(3) % Fixing the final look

The solution with NaN's is the correct...!

I'm practicing my english and learning Matlab..! What more can I ask? :-D

On Apr 28, 7:50 am, Ray <rbenber...@yahoo.com> wrote:
> I have the x-y-z coordinates of a set of points which I'd like to plot
> as a 3-D surface. At some coordinates, the points do not exist. The
> plotted surface should therefore show gaps or 'holes' in areas where
> points are missing. I've tried the 'surf' command but that doesn't
> render the desired surface. I found that 'surf' fits a nice smooth
> surface over the points while interpolating between the points, hence
> filling in those 'holes'.
> Is there a another Matlab command or any way in Matlab to get the plot
> I'm after ? Thanks a lot for your help.
>
> Ray


Thank you guys for your help. NaN works beautifully.

Ray <rbenbernou@yahoo.com> wrote in message <14c1f967-6172-4e2d-9772-855a7f2c48ba@b7g2000pre.googlegroups.com>...
> On Apr 28, 7:50 am, Ray <rbenber...@yahoo.com> wrote:
> > I have the x-y-z coordinates of a set of points which I'd like to plot
> > as a 3-D surface. At some coordinates, the points do not exist. The
> > plotted surface should therefore show gaps or 'holes' in areas where
> > points are missing. I've tried the 'surf' command but that doesn't
> > render the desired surface. I found that 'surf' fits a nice smooth
> > surface over the points while interpolating between the points, hence
> > filling in those 'holes'.
> > Is there a another Matlab command or any way in Matlab to get the plot
> > I'm after ? Thanks a lot for your help.
> >
> > Ray
>
>
> Thank you guys for your help. NaN works beautifully.


Hi, I am doing the same thing myself using NaN to make holes in my surf plot. But rather than have these undefined regions white with grid lines, I would like it to be grey. I thought I could do it in illustrator by putting a grey square behind the surf plot, but of course this won't work as the color map doesn't de-group that way...

Is there an easy solution i'm missing here??

Adam

Ray <rbenbernou@yahoo.com> wrote in message <14c1f967-6172-4e2d-9772-855a7f2c48ba@b7g2000pre.googlegroups.com>...
> On Apr 28, 7:50 am, Ray <rbenber...@yahoo.com> wrote:
> > I have the x-y-z coordinates of a set of points which I'd like to plot
> > as a 3-D surface. At some coordinates, the points do not exist. The
> > plotted surface should therefore show gaps or 'holes' in areas where
> > points are missing. I've tried the 'surf' command but that doesn't
> > render the desired surface. I found that 'surf' fits a nice smooth
> > surface over the points while interpolating between the points, hence
> > filling in those 'holes'.
> > Is there a another Matlab command or any way in Matlab to get the plot
> > I'm after ? Thanks a lot for your help.
> >
> > Ray
>
>
> Thank you guys for your help. NaN works beautifully.


Hi, I am doing the same thing myself using NaN to make holes in my surf plot. But rather than have these undefined regions white with grid lines, I would like it to be grey. I thought I could do it in illustrator by putting a grey square behind the surf plot, but of course this won't work as the color map doesn't de-group that way...

Is there an easy solution i'm missing here??

Adam