[Proj] PROJ 4.5.0 beta (and Krovak!)

Clifford J Mugnier cjmce at lsu.edu
Wed Oct 18 19:05:23 EDT 2006

"Historical Military Mapping of Czech Lands - Positional Accuracy of Old
Maps" by Zimova, Pestak, and Veverks is in the current (October 2006) issue
of "GIM International" magazine, pp 21-23.

Nice article, but no test points - just examples of the magnitudes of the

Cliff Mugnier
> From: "Gerald I. Evenden"
> Date: Wed, 18 Oct 2006 11:43:38 -0400
> Subject: Fwd: Re: [Proj] PROJ 4.5.0 beta (and Krovak!)

>> While proj produces results, though I don't know how correct they are:
>> warmerda at gdal2200[1926]% ./proj +proj=krovak +ellps=bessel
>> 10 45
>> -1164802.15     -1546506.69

For lat=45, lon=10, wrt Greenwich, I got:
1546506.69219, 1164802.14778
Keep in mind that Krovak is South/West oriented.
The axis called X-axis runs from north to south, the Y-axis runs from east
to west.

>> I don't really know any test points for Krovak or even what options
>> are required in the two implementations.

There are two reasonably trustworthy test points published.

Test point from the EPSG Guidance Note 7.2:
lat="50 12 32.4416"; lon="16 50 59.1790"; // wrt Greenwich, d m s format
y,x: 1050538.64314, 568990.99673
published values: 1050538.643, 568990.997 m

Test point from "Krovak Projection", B. Veverka, Czech Technical University
- Department of Mapping and Cartography:
The coordinates are with respect to Ferro at -17d 40m (wrt Greenwich).
lat="48 7 46.2973"; lon="35 42 35.2147";
y,x: 1289068.72401, 504691.67509
published values: 1289068.724, 504691.675 m

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