Bits-Back Coding

Problem

Return the total description length in bits of a bits-back code:

length = nll_bits + kl_bits

where nll_bits is the negative log-likelihood and kl_bits the KL divergence from the posterior to the prior.

Hint

A tighter posterior (smaller KL) shortens the code.

case 1

in: [10,2]

expected: 12

case 2

in: [0,0]

expected: 0

case 3

in: [5.5,1.5]

expected: 7

case 4

in: [3,0]

expected: 3

Starter codePython

def bits_back_coding(nll_bits, kl_bits):
    # Your code here
    pass

4 test cases · run your code against them in the editor