[Proj] Lambert Azimuthal Equal Area scale

Lourens Veen l.e.veen at uva.nl
Thu Jun 11 09:22:28 EST 2015

On 10/06/15 17:41, Lourens Veen wrote:
> I'll check everything again tomorrow, this time with lon and lat in the
> right order for invgeod to understand it correctly. I agree that geod
> should be fixed, both geod and proj are libproj utilities, they should
> correctly interpret each other's default output format.

Well, I reversed lat and lon, and I'm getting much more reasonable 
results now. I'm still getting a discrepancy between GeographicLib and 
proj though:

proj 4.8.0:	(Ubuntu package)

$ invgeod +ellps=WGS84 +units=m
43.948780899203733 -153.87240094587023 44.036369120054417 
-26d7'4.466"	153d50'26.145"	10861.026

GeographicLib-1.42	(from source)
$ GeodSolve -i
43.948780899203733 -153.87240094587023 44.036369120054417 
-26.19689664 -26.23839343 10848.141

For my purposes, a 15m difference is not such a problem, but I'd like to 
be sure that this is a precision issue, rather than a mistake on my part 
somewhere. Perhaps this is why there's a new backend in 4.9.0?



ir. Lourens Veen - PhD Student - UvA-IBED-CGE
    m: P.O. Box 94248, NL-1090 GE  Amsterdam
              t: +31 (0)20-5258293

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