Matlab 3D Plot（surf）自动填充空白

Question

I'm using surf() to plot a portion of a sphere; basically a shell of a certain shape that is on top of a sphere. More specifically, it is the workspace plot of spherical joint with color representing the resolution of the joint at that point.

Anyways, the shape is unique, but surf() automatically fills in gaps that should not be there. I'm guess it might be the order that it is plotted? Is there any way to prevent Matlab from doing this?

I think it is obvious in the pictures what should not be there:

Also, it seems to mess up the color coding as well. The dark blue should be at the bottom edges of the shell; instead Matlab assigns it to the surface used to fill the gaps.

Answer 1

The following code achieves what I think you are asking (namely - making part of a surface plot "invisible", which I do by defining a matrix transp of the same dimensions as zz , with alpha values (1=visible, 0=transparent). Of course you will have to change your definition of transp to match the parts of the surface you don't want to see - my simple clipping method is just to show what can be done):

[xx yy]=meshgrid(linspace(-1,1,200));
zz = 1./(xx.^2 + yy.^2 + 0.5);
theta = atan2(yy,xx);
r = sqrt(xx.^2 + yy.^2);
transp = double(r < (0.3*cos(6*theta)+0.6));
figure
surf(xx,yy,zz,'edgecolor','none','FaceAlpha', 'interp', 'AlphaData', transp);

This gives the following plot:

I trust you can figure it out from here. If this doesn't work you need to give more information about the data you have - what is the size, how are you plotting it...