Introduction
This blog is the theory for https://github.com/0382/CGcoefficient.jl.
It is mainly inspired by Ref[1]. See Jensen’s code for details.
The idea is to simplify 3nj Symbols to sum combinations of binominal coefficients. We can calculate binominal coefficients by Pascal’s Triangle, and store them first. Then we calculate 3nj Symbols using the stored binominal coefficients.
My code is just a toy model, using Julia’s own binominal
function, and use BigInt
to get absolute results. If you want to get the exact result, and you don’t use it for numeric computing, it is really a good package.