[OSRS-PROJ] Bug in CEA projection?

[David Orme]

Ah - sorry, I didn't get the difference. I've downloaded libproj4 - had 
a few problems building lproj because the proj4 library was masking the 
libproj4 versions and so I got undefined symbols for _pj_dmstor, 
_pj_rtodms and _pj_set_rtodms.  I changed the Makefile for libproj4 to 
build to libproj4.a rather than libproj.a and then the library linker 
flag in make lproj to -lproj4 - that gives me a working version that 
gives the correct answer:

> doibook:/usr/local/src/libproj4/source dorme$ ./lproj +proj=cea 
> +ellps=WGS84 +lat_ts=30 -I -f '%.6f'<<EOF
> >  0 7284713.234
> > EOF
> 0.000000        82.855347
> doibook:/usr/local/src/libproj4/source dorme$

Thanks for your help - I'll post this as a bug with solution...

Thanks,
David

On 28 Jan 2004, at 16:51, Gerald Evenden wrote:

> I think the problem is what source?  The last libproj4 release was
> April, '03 which would have caught the version I used in the test
> of my previous email.
>
> Unfortunately, the remotesensing.org site does not use libproj4.
>
> I expect to make a new release in the near future once the 
> documentation
> and final cleanup of Oblique Mercator (Hotine) are completed.
>
> On Jan 28, 2004, at 11:17 AM, David Orme wrote:
>
>> That's odd - I've just recently compiled proj4 from source but I 
>> still get the wrong answer.
>>
>>> doibook:~ dorme$ proj +proj=cea +ellps=WGS84 +lat_ts=30 -I -f 
>>> '%.6f'<<EOF
>>> > 0 7284713.234
>>> > EOF
>>> 0.000000        82.485563
>>> doibook:~ dorme$ proj
>>> Rel. 4.4.7, 31 March 2003
>>> usage: proj [ -beEfiIlormsStTvVwW [args] ] [ +opts[=arg] ] [ files ]
>>> doibook:~ dorme$
>>
>> The linker details from the dynamic library are:
>>
>>> doibook:~ dorme$ otool -L /usr/local/lib/libproj.dylib
>>> /usr/local/lib/libproj.dylib:
>>>         /usr/local/lib/libproj.0.dylib (compatibility version 5.0.0, 
>>> current version 5.1.0)
>>>         /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, 
>>> current version 71.0.0)
>>
>> Am I using an outdated version?
>>
>> Thanks,
>> David
>>
>> On 28 Jan 2004, at 15:18, Gerald Evenden wrote:
>>
>>> Local lproj (libproj4) script:
>>>
>>> ../lproj +proj=cea +ellps=WGS84 +lat_ts=30 -I -f '%.6f'<<EOF
>>> 0 7284713.234
>>> EOF
>>>
>>> Produces the following results:
>>>
>>> 0.000000	82.855347
>>>
>>> Older versions of proj seem to have a problem.  Last change
>>> to cea (libproj4) was Mar., '03
>>>
>>> On Jan 28, 2004, at 6:00 AM, Orme, David wrote:
>>>
>>>> Hi,
>>>>
>>>> This was cross-posted from the Grass list a while back - have I got
>>>> something wrong or is this a bug?
>>>>
>>>> I'm using Proj 4.4.7 on my Mac 10.3.2 and ArcGIS 8 on a Windows XP
>>>> machine - the two programs give different answers for coordinate
>>>> transformations into  a Behrmann projection (Cylindrical Equal Area
>>>> with latitude of true scale at 30 N/S). I've checked using Geotrans
>>>> 2.2.4 on the Windows machine and that agrees with ArcGIS.
>>>>
>>>> My test point is in Behrmann coordinates, units in meters: 0E
>>>> 7284713.234N
>>>>
>>>> cs2cs gives:
>>>>
>>>> > doibook:~/Library/Preferences dorme$ cs2cs -f "%0.6f" +proj=cea
>>>> > +lat_ts=30 +datum=WGS84 +to +proj=latlong +datum=WGS84
>>>> > 0 7284713.234
>>>> > 0.000000        82.485563 0.000000
>>>>
>>>> Both ArcGIS and Geotrans give the following geodesic coordinates: 0 
>>>> E
>>>> 82.855347 N
>>>>
>>>> Any suggestions?
>>>>
>>>> Many thanks,
>>>> David Orme
>>>>
>>>>
>>>>
>>> _____________________________________
>>> Jerry and the low riders: Daisy Mae and Joshua
>>
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> _____________________________________
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>
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