Calculates distance between two points on earth using their latitudes and longitudes

haversian_distance.py

#!/usr/bin/env python3
'''Calculates Haversian distance between two points on earth'''

from math import (sqrt, radians, sin, cos, atan2)

def haversian_dist(loc1, loc2):
    '''Calculates Haversian distance between two points on earth
       loc1 and loc2 are (lat, long) of two points'''
    
    radius = 6373.0     # approx earth radius in km

    lat1, lon1, lat2, lon2 = map(radians, loc1 + loc2)
    lon_diff, lat_diff = lon2 - lon1, lat2 - lat1

    a = sin(lat_diff / 2)**2 + cos(lat1) * cos(lat2) * sin(lon_diff / 2)**2

    distance = radius * 2 * atan2(sqrt(a), sqrt(1 - a))

    return distance