I saw a function defined something like the following:
f[n_Integer][r, θ] = Sin[n r π/L] Cos[n r L π θ/4]
My question is, why did my professor define the function like above, instead of using
f[n_Integer, r_, θ_]? What is the difference? I could not find any answers on Mathematica, or google, or here.
If this has been asked before,and I did not find it, I apologize.