For sphere Snyder describes generating formulae for the projection, as well as the projection's characteristics. Coordinates from a spherical
datum can be transformed into Albers equal-area conic projection coordinates with the following formulas, where {R} is the radius, \lambda is the longitude, \lambda_0 the reference longitude, \varphi the latitude, \varphi_0 the reference latitude and \varphi_1 and \varphi_2 the standard parallels: : \begin{align} x &= \rho \sin\theta, \\ y &= \rho_0 - \rho \cos\theta, \end{align} where : \begin{align} n &= \tfrac12 (\sin\varphi_1 + \sin\varphi_2), \\ \theta &= n (\lambda - \lambda_0), \\ C &= \cos^2 \varphi_1 + 2 n \sin \varphi_1, \\ \rho &= \tfrac{R}{n} \sqrt{C - 2 n \sin \varphi}, \\ \rho_0 &= \tfrac{R}{n} \sqrt{C - 2 n \sin \varphi_0}. \end{align}
Lambert equal-area conic If just one of the two standard parallels of the Albers projection is placed on a pole, the result is the
Lambert equal-area conic projection. ==See also==