Richardson Extrapolation

Problem

Richardson extrapolation cancels the leading O(h^2) error term of a numerical approximation.

Given two estimates d_h and d_half computed with step sizes h and h/2, return the extrapolated value (4*d_half - d_h) / 3.

Hint

The weights 4/3 and -1/3 eliminate the h squared term.

case 1

in: [1.1,1.025]

expected: 0.9999999999999999

case 2

in: [0.26,0.065]

expected: 0

case 3

in: [1,1]

expected: 1

case 4

in: [2,1.5]

expected: 1.3333333333333333

Starter codePython

def richardson(d_h, d_half):
    # Your code here
    pass

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