npts = 70000;
th = 2*pi*rand(npts,1);
r = 5+rand(npts,1)/3;
v = randn(npts,1);
[x,y,z] = pol2cart(th,r,v);
c = v;
scatter3(x,y,z,8,c,'.')
axis equal
view(-65,42)
You don't get a polar grid with this approach though. If you need that, I think that there are some options on the File Exchange .