import math


def gaussian(x, mean, sdev):
    """ Computes a gaussian """
    first, second = 0, 0
    if sdev > 0:
        first = 1 / (math.sqrt(2 * math.pi) * sdev)
        second = math.e ** (-((x - mean) ** 2) / (2 * (sdev ** 2)))
    return first * second