Best way to define the characteristic/indicator function of a square?

Hi,

I was wondering if there is not a better way (shorter) to define a characteristic/indicator function of a square/cube than with the function "flc1hs". Indeed, when I use flc1hs (or one of his declination i.e flc2hs) in 2d or 3d and for my specific problem, I got a lot of these functions.

Example in 2d : Let's say that we want to implement the indicator function of , I write flc1hs(x-0.2,0.01)* flc1hs(0.4-x,0.01)* flc1hs(y,0.01)* flc1hs(0.2-y,0.01).

Thanks