Elo Update Magnitude

Problem

Return the Elo rating change k * (score - expected) for a game where score is 1.0 for a win, 0.5 for a draw, and 0.0 for a loss. The expected score uses the standard 400-point logistic scale.

Test cases

case 1

in: [1500,1500,1,32]

expected: 16

case 2

in: [1500,1500,0,32]

expected: -16

case 3

in: [1600,1400,1,16]

expected: 3.8440491736326745

case 4

in: [1600,1400,1,0]

expected: 0

Starter codePython

def elo_update(ra, rb, score, k):
    # Your code here
    pass

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