[Help-gsl] Spherical Harmonics

[Peng Yu]

Hi,

I am trying to use spherical harmonics descriptors. So I need a function to 
give me the value of Y_lm for each input of (theta, phi). Therefore, I was 
hoping I could use the Legendre function in your library.

Ideally I hope that Legendre function could give me a value P_lm(cos(theta)). 
But I did not see anything close to that in the library. Could you help me 
out? Thanks a lot for your effort!

Best,
Peng