Run-Length Encoded Entropy

Problem

Run-length encode s and return the empirical Shannon entropy in bits of the run-length values, where each run contributes one sample. Return 0.0 for the empty string. Compute the runs first, then take the entropy of their value distribution.

Hint

A constant run-length distribution means the run-length code carries no information.

Test cases

case 1

in: ["aaabbbcc"]

expected: 0.9182958340544896

case 2

in: ["aaabbc"]

expected: 1.584962500721156

case 3

in: ["aaaa"]

expected: 0

case 4

in: ["aabbaabb"]

expected: 0

case 5

in: ["abab"]

expected: 0

Starter codePython

import math
def rle_entropy(s):
    # Your code here
    pass

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