Page 44 - Basics of MATLAB and Beyond

hold on
plot3(x(ind),y(ind),z(ind),’.’)

The x, y domain of the extracted points can be shown clearly with an
overhead view:

view(2)
xyz
shading flat

The associated z values can be shown with a side view:

view(90,0)
grid

7.6 Nonrectangular Surface Domains

The polarmesh function given on page 26 showed a conical function
defined over a circular domain of x and y points. Let us now look a
bit more generally at how to define such nonrectangular domains for
surfaces.
The standard matlab functions, including graphics functions, tend
to like working with rectangular matrices: each row must have the same
number of columns. For surfaces, this requirement applies to the x, y
and z matrices that specify the surface. Let us demonstrate by way of
an example. First we generate a rectangular domain of x and y points,
with x going from −1to1,and y going from 0 to 2:

>> [x,y] = meshgrid(-1:1,1:3)

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