r =

 theta start (radians)

 theta finish (radians)

 r max

Functions available in JavaScript are abs(x), acos(x), asin(x), atan(x), ceil(x), cos(x), exp(x), floor(x), log(x), max(x,n), min(x,n), pow(x,n), random(), round(x), sin(x), sqrt(x) and tan(x).

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