Rolling Population Standard Deviation

Problem

Return the population standard deviation (denominator equals window) of every consecutive window of length window. Return an empty list when window <= 0 or window > len(data).

Hint

Same windows as a rolling mean, but return the square root of the population variance.

Test cases

case 1

in: [[1,2,3,4,5],3]

expected: [0.816496580927726,0.816496580927726,0.816496580927726]

case 2

in: [[2,2,2],2]

expected: [0,0]

case 3

in: [[1,2],2]

expected: [0.5]

case 4

in: [[1,2,3,4],2]

expected: [0.5,0.5,0.5]

case 5

in: [[10,12,14,16,18],3]

expected: [1.632993161855452,1.632993161855452,1.632993161855452]

Starter codePython

def rolling_std(data, window):
    # Your code here
    pass

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