Function rgsl::coupling_coefficients::_3j

pub fn _3j(
    two_ja: i32, 
    two_jb: i32, 
    two_jc: i32, 
    two_ma: i32, 
    two_mb: i32, 
    two_mc: i32
) -> f64

This routine computes the Wigner 3-j coefficient,

(ja jb jc ma mb mc)

where the arguments are given in half-integer units, ja = two_ja/2, ma = two_ma/2, etc.