I found that I needed compass bearing to get the correct direction for my distance. For bearing I found compassbearing.py @ https://gist.github.com/jeromer/2005586
The inputs of which are pointA, pointB). Output is bearing. From there I can use geopy Point and geopy.distance vincenty to figure out the distance and subsequent new coordinate.
import math
from geopy import Point
from geopy.distance import vincenty
def calculate_initial_compass_bearing(pointA, pointB):
"""
Calculates the bearing between two points.
The formulae used is the following:
θ = atan2(sin(Δlong).cos(lat2),
cos(lat1).sin(lat2) −
sin(lat1).cos(lat2).cos(Δlong))
:Parameters:
- `pointA: The tuple representing the
latitude/longitude for the
first point. Latitude and longitude must be in
decimal degrees
- `pointB: The tuple representing the latitude/longitude for the
second point. Latitude and longitude must be in decimal degrees
:Returns:
The bearing in degrees
:Returns Type:
float
"""
if (type(pointA) != tuple) or (type(pointB) != tuple):
raise TypeError("Only tuples are supported as arguments")
lat1 = math.radians(pointA[0])
lat2 = math.radians(pointB[0])
diffLong = math.radians(pointB[1] - pointA[1])
x = math.sin(diffLong) * math.cos(lat2)
y = math.cos(lat1) * math.sin(lat2) - (math.sin(lat1)
* math.cos(lat2) * math.cos(diffLong))
initial_bearing = math.atan2(x, y)
# Now we have the initial bearing but math.atan2 return values
# from -180° to + 180° which is not what we want for a compass bearing
# The solution is to normalize the initial bearing as shown below
initial_bearing = math.degrees(initial_bearing)
compass_bearing = (initial_bearing + 360) % 360
return compass_bearing
b = calculate_initial_compass_bearing((44.27364400, -121.17116400),(44.27357900, -121.17006800))
distKm = .01
lat1 = 44.27364400
lon1 = -121.17116400
vincenty(kilometers=distKm).destination(Point(lat1, lon1), 94.73454666253849).format_decimal())
