An Alternative Scheme for the Summation of a Series of Spherical Harmonics
Philip E. Merilees · Journal of applied meteorology · 1973
An alternative algorithm to sum a series of spherical harmonies is presented and tested. The algorithm is approximately 10–20 times faster than a standard method under the condition that both start with only the knowledge of the coefficients. The algorithm does suffer from a precision problem and breaks down when the resolution is too high.