def nfwd

bend-ml-autograd@0.1.1.0 · main.bend:41

import Base

41# FORWARD-mode derivative (dual numbers): derivative of the sum and the product rule
42def nfwd(e: NE, +x: Nat) -> Nat:
43  match e:
44    case NCst{n}:
45      0n
46    case NX{}:
47      1n
48    case NAdd{a, b}:
49      Nat.add(nfwd(a, x), nfwd(b, x))
50    case NMul{+a, +b}:
51      Nat.add(Nat.mul(nfwd(a, x), nval(b, x)), Nat.mul(nval(a, x), nfwd(b, x)))