Best way to calculate distance between geographicalpoints

On Thu, 14 Jan 2010 12:27:04 +0100 (CET) Roger Bivand

So in principle geod.dist() and spDistsN1(..., longlat=TRUE) should yield 
equivalent results, because their assumptions are the same.

Several of the references suggest that the geographic pole should not be 
input. It looks as though the oce implementation handles this more 
gracefully than sp.

Hope this helps,

It does. Thanks.

BTW, is there a reason 'spDistsN1' handle longitude 360 different from 
longitude 0? For example, the distance between 0,0 and 0,0 is 0, but the 
distance between 0,0 and 360,0 is about 1e-12. This is of course not a 
problem; I was just wondering on the reason (since 360,0 is for all 
practical *correctly* handled -- it's just not handled equal to 0,0).

Karl Ove Hufthammer