Bipolar coordinates are a two-dimensional system of coordinates. There are two commonly defined types of bipolar coordinates, the first of which is defined by x | = | (a sinh v)/(cosh v - cos u) y | = | (a sin u)/(cosh v - cos u), where u element [0, 2π), v element (-∞, ∞). The following identities show that curves of constant u and v are circles in x y-space. x^2 + (y - a cot u)^2 = a^2 csc^2 u (x - a coth v)^2 + y^2 = a^2 csch^2 v.

bipolar cylindrical coordinates | polar coordinates