[OSRS-PROJ] Bug in CEA projection?

[David Orme]

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Am I using an outdated version?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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