[Bug] Incorrect distance when longitude close to antimeridian

[johnp-4dvanalytics]

inverse(lats1=[0], lons1=[179.9999999], 
        lats2=[0], 
        lons2=[180])["s12"]
        
#array([20003931.4586233])

the below code fixes it:

def fix_lon(x, dtype=np.float64):
    min_lon = -180 + np.finfo(dtype).eps
    max_lon = 180 - np.finfo(dtype).eps 
    
    x = np.where(x > max_lon, max_lon, x)
    x = np.where(x < min_lon, min_lon, x)
    return x

inverse(lats1=[0], lons1=fix_lon([179.9999999]), 
        lats2=[0], 
        lons2=fix_lon([180]))["s12"]

#array([0.])

[omdv]

Thanks for finding this. I checked your proposed fix and I don't think it will work, first of all it does not solve the issue for me as-is if I do proper comparison vs geographiclib (non-vectorized benchmark) and also there are some further test issues.

Looking into it. The problem goes away if you increase the separation between points. So just want to mention that you are pushing accuracy of WGS84 geod model if you want to go to centimeters.

[omdv]

I introduced the fix and added new tests. Please check the new version from pip (==1.3).