Effects: These functions compute the spherical associated Legendre functions
of their respective arguments
l, m, and theta (theta measured in radians).
Returns: Yβm(ΞΈ,0)
where
Yβm(ΞΈ,Ο)=(β1)m[(2β+1)4Ο(ββm)!(β+m)!]1/2Pβm(cosΞΈ)eimΟΒ , forΒ |m|β€β,
and
l is l,
m is m, and
ΞΈ is theta.