It is indeed confusing. You can plot the far field in spherical coordinate like this:

polarimage(ux,uy,E2);

Phi is from 0 to 360 deg and theta is from -90 to 90. So how can you cut the image into a 2D polar plot? phi=0 is only from theta from 0 to 90, and phi=180 gives theta from -90 to 0.

There is a little complicated, subtle issue here. If you have premium support previledge, please send us support ticket for more.

Or simply use

polarimage(ux,uy,E2);

to plot the 3D result.