[Proj] PROJ 4.5.0 beta (and Krovak!)

Frank Warmerdam warmerdam at pobox.com
Tue Oct 17 16:41:49 EDT 2006


Gerald I. Evenden wrote:
> I do not particularly care what the projection is called but I would 
> appreciate some communications as to using the 'kocc' designation so I could 
> at least change my releases of libproj4 to conform with external usage.

Gerald,

OK, I've gone back over this, thinking to modify PROJ.4 to support either
name (proj=krovak or proj=kocc) similarly.  However, I've come to the
conclusion there must be some other differences in the defaults, orientation
or something for these two implementations of the projection.

In particular, for a test point at 10E, 45N, lproj seems to fail:

warmerda at gdal2200[917]% ./lproj +proj=kocc +ellps=bessel
10 45
nan     -inf

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

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

For now, I'll stick with the existing Krovak code for the 4.5.0 release,
but if there are things we can do to make the two implementations
compatible with the aim of a seamless transition to use of libproj4
in the future, I'd be all for that!

PS. I see PJ_krovak was checked in sometime in 2002.

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGeo, http://osgeo.org



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