Successor to geofun C++ and python library for doing geographic calculations like distance, azimuth and position determination for geodesics and rhumb lines, orthodromes and loxodromes, respectively.

This version makes use of GeographicLib for doing most of the calculations.

Currently only building on linux is supported. You'll need c++, make and cmake. When you have those, you should be able to run:

make build && make install

You should also be able to add this module to your python project's virtual environment by add the following to your requirements.txt:

git+https://github.com/jrversteegh/geofun2.git@master#egg=geofun2

pip install -r requirements.txt should then automatically install geofun2 in your virtual environment.

from geofun2 import Position, Vector

# Just off Hoek van Holland
org = Position(52.0, 4.0)
nm95 = 95 * 1852.0

# Go west 95 nm to Felixstowe
rmbv = Vector(270.0, nm95)
pos1 = org + rmbv

# Go to the same point using great circle line
gcv = pos1 / org
pos2 = org * gcv

# We should end up at the same location
assert pos1 == pos2

# How disappointing: we managed to gain just 9m by crossing the
# North sea using a great circle :p
assert nm95 - gcv.length == 9.101067085022805, f'Unexpected: {gcv.length}'

print(f'From {org} to {pos1}')
print(f'Rhumb: {rmbv}')
print(f'Great circle: {gcv}')

# Another verification
assert pos1 - org == rmbv
assert pos1 / org == gcv

Position

• latitude
• longitude

Vector

• azimuth
• length

Point

• x
• y

get_version() -> str

Get the library version

geodesic_direct(latitude: float, longitude: float, azimuth: float, distance: float) -> tuple

Get position and final azimuth after moving distance along great circle with starting azimuth

geodesic_inverse(latitude: float, longitude: float, azimuth: float, distance: float) -> tuple

Get starting azimuth, distance and ending azimuth of great circle between positions

rhumb_direct(latitude: float, longitude: float, azimuth: float, distance: float) -> tuple

Get position and final azimuth after moving distance from starting position at fixed azimuth/along rhumb line

rhumb_inverse(latitude1: float, longitude1: float, latitude2: float, longitude2: float) -> tuple

Get rhumb line azimuth, distance and final azimuth between positions

angle_diff(arg0: numpy.ndarray[numpy.float64], arg1: numpy.ndarray[numpy.float64]) -> object

Signed difference between to angles

angle_mod(arg0: numpy.ndarray[numpy.float64]) -> object

Return angle bound to [0.0, 360.0>

angle_mod_signed(arg0: numpy.ndarray[numpy.float64]) -> object

Return angle bound to [-180.0, 180.0>