py3nj.wigner9j

py3nj.wigner9j(two_l1, two_l2, two_l3, two_l4, two_l5, two_l6, two_l7, two_l8, two_l9)

Calculate wigner 9j symbol (L1 L2 L3) (L4 L5 L6) (L7 L8 L9)

defined as

2x (a b c) (d e f) (g h j)

sum_x (-1) (2x+1) (f j x) (b x h) (x a d)

2x (x f b) (x h b) (x a j)

sum_x (-1) (2x+1) (c a j) (e f d) (g h d)

Parameters

two_l1: array of integers

two_l2: array of integers

two_l3: array of integers

two_l4: array of integers

two_l5: array of integers

two_l6: array of integers

two_l7: array of integers

two_l8: array of integers

two_l9: array of integers

Since L1, …, L9 should be integers or half integers, two_l1 (which means 2 x L1) should be all integers.

Returns

threej: array

The value of 9J symbol with the same shape of the arguments.