@contract
def variance(data, window_size):
    m = mean(data, window_size)
    return float(sum((x - m) ** 2 for x in data)) / (window_size - 1)
Get the data variance according to the window size.
dataset/ETHPy150Open beloglazov/openstack-neat/neat/locals/overload/mhod/multisize_estimation.py/variance