libpysal.cg.geointerpolate

libpysal.cg.geointerpolate(p0, p1, t, lonx=True)[source]

Finds a point on a sphere along the great circle distance between two points on a sphere also known as a way point in great circle navigation

Parameters
p0first point as a tuple in decimal degrees
p1second point as a tuple in decimal degrees
tproportion along great circle distance between p0 and p1

e.g., t=0.5 would find the mid-point

lonxbool to assess the order of the coordinates,

for lon,lat (default) = True, for lat,lon = False

Returns
x,ytuple in decimal degrees of lon-lat (default) or lat-lon,

depending on setting of lonx; in other words, the same order is used as for the input

Examples

>>> p0 = (-87.893517, 41.981417)
>>> p1 = (-87.519295, 41.657498)
>>> geointerpolate(p0,p1,0.1)          # using lon-lat
(-87.85592403438788, 41.949079912574796)
>>> p3 = (41.981417, -87.893517)
>>> p4 = (41.657498, -87.519295)
>>> geointerpolate(p3,p4,0.1,lonx=False)   # using lat-lon
(41.949079912574796, -87.85592403438788)