["python","gis","distance","latitude-longitude"]
Get lat/long given current point, distance and bearing

Given an existing point in lat/long, distance in (in KM) and bearing (in degrees converted to radians), I would like to calculate the new lat/long. This site crops up over and over again, but I just can't get the formula to work for me. The formulas as taken the above link are: lat2 = asin(sin(lat1)*cos(d/R) + cos(lat1)*sin(d/R)*cos(θ)) lon2 = lon1 + atan2(sin(θ)*sin(d/R)*cos(lat1), cos(d/R)−sin(lat1)*sin(lat2)) The above formula is for MSExcel where- asin = arc sin() d = distance (in any unit) R = Radius of the earth (in the same unit as above) and hence d/r = is the angular distance (in radians) atan2(a,b) = arc tan(b/a) θ is the bearing (in radians, clockwise from north); Here's the code I've got in Python. import math R = 6378.1 #Radius of the Earth brng = 1.57 #Bearing is 90 degrees converted to radians. d = 15 #Distance in km #lat2 52.20444 - the lat result I'm hoping for #lon2 0.36056 - the long result I'm hoping for. lat1 = 52.20472 * (math.pi * 180) #Current lat point converted to radians lon1 = 0.14056 * (math.pi * 180) #Current long point converted to radians lat2 = math.asin( math.sin(lat1)*math.cos(d/R) + math.cos(lat1)*math.sin(d/R)*math.cos(brng)) lon2 = lon1 + math.atan2(math.sin(brng)*math.sin(d/R)*math.cos(lat1), math.cos(d/R)-math.sin(lat1)*math.sin(lat2)) print(lat2) print(lon2) I get lat2 = 0.472492248844 lon2 = 79.4821662373
Needed to convert answers from radians back to degrees. Working code below: from math import asin, atan2, cos, degrees, radians, sin def get_point_at_distance(lat1, lon1, d, bearing, R=6371): """ lat: initial latitude, in degrees lon: initial longitude, in degrees d: target distance from initial bearing: (true) heading in degrees R: optional radius of sphere, defaults to mean radius of earth Returns new lat/lon coordinate {d}km from initial, in degrees """ lat1 = radians(lat1) lon1 = radians(lon1) a = radians(bearing) lat2 = asin(sin(lat1) * cos(d/R) + cos(lat1) * sin(d/R) * cos(a)) lon2 = lon1 + atan2( sin(a) * sin(d/R) * cos(lat1), cos(d/R) - sin(lat1) * sin(lat2) ) return (degrees(lat2), degrees(lon2),) lat = 52.20472 lon = 0.14056 distance = 15 bearing = 90 lat2, lon2 = get_point_at_distance(lat, lon, distance, bearing) # lat2 52.20444 - the lat result I'm hoping for # lon2 0.36056 - the long result I'm hoping for. print(lat2, lon2) # prints "52.20451523755824 0.36067845713550956"