Kata

Background

Moving average of a set of values and a window size is a series of local averages.

Example:

Values: [1, 2, 3, 4, 5]
Window size: 3

Moving average is calculated as:


 1, 2, 3, 4, 5
 |     |
 ^^^^^^^
 (1+2+3)/3 = 2
 
 
  1, 2, 3, 4, 5
     |     |
     ^^^^^^^
     (2+3+4)/3 = 3
 
 
  1, 2, 3, 4, 5
        |     |
        ^^^^^^^
        (3+4+5)/3 = 4
 
Here, the moving average would be [2, 3, 4]

Task

Given a list values of integers and an integer n representing size of the window, calculate and return the moving average.

When integer n is equal to zero or the size of values list is less than window's size, return None

Reference: Moving average