### "and zero everywhere else"

I'm trying to create a symbolic function in two variables that returns cos(x)cos(y) for -pi/2<=x<=pi/2 and -pi/2<=y<=pi/2, and zero everywhere else.

I've dug around in the piecewise documentation and I'm running up against a few limitations:

-- no infinite intervals prevents the "everywhere else" construct.

-- I don't think there's a way to express the fact that 3*pi/2 == -pi/2

-- I haven't had much luck defining a piecewise function in two variables.

Is there a way to do this, or am I doomed to a python function and if/else statements?

Thanks--

Greg