[Proj] Polar stereographic, different values on different platforms?

[Bruce Raup]

Frank and all,

Has the problem described in the below been resolved yet?  A colleague
of mine and I have just executed the same "proj" command on Windows
and Linux, and are getting different results.  Windows version is Rel.
4.6.1, 21 Jul 2008.  Linux versions are Rel. 4.5.0, 22 Oct 2006 and
Rel. 4.6.0, 21 Dec 2007

Command:
echo "105 40" | proj +proj=stere +lat_0=90 +lon_0=0 +lat_ts=70 +datum=WGS84

On both Linux boxes, we get the output
5577808.93      1494569.40

On Windows, my colleague gets:
5610189.12      1503245.64

Using GMT's "mapproject" program, I get the same results as the Linux
versions of Proj:
echo "105 40" | mapproject -Js0/90/70/1:1 -C -F -R-180/180/30/90
5577808.933369  1494569.399231

What is the cause the the problem?  There is no change when we specify
'+ellps=WGS84'.  I searched my archive of the list and found the
below.

Thanks in advance for any insight,
Bruce Raup

On Tue, Jun 5, 2007 at 11:22 AM, Frank Warmerdam <warmerdam at pobox.com> wrote:
> aaime74 wrote:
>>
>> Hi,
>> at Geoserver we're experiencing some issues with projection code, and we
>> took Proj as
>> an external reference for comparison.
>> Well, it turns out that proj 4.5 returns different results when compiled
>> for
>> Windows
>> and Linux.
>>
>> On Linux:
>> desruisseaux at adagio ~ $ proj
>> Rel. 4.5.0, 22 Oct 2006
>> usage: proj [ -beEfiIlormsStTvVwW [args] ] [ +opts[=arg] ] [ files ]
>> desruisseaux at adagio ~ $ proj +proj=stere +lon_0=-96.0 +lat_0=90 +lat_ts=71
>> +ellps=WGS84 +datum=WGS84
>> -121.33955 39.1012523
>> -2529570.00     -5341800.00
>>
>> On Windows:
>> C:\Program Files\FWTools1.1.3>proj
>> Rel. 4.5.0, 22 Oct 2006
>> usage: proj [ -beEfiIlormsStTvVwW [args] ] [ +opts[=arg] ] [ files ]
>>
>> C:\Program Files\FWTools1.1.3>proj +proj=stere +lon_0=-96.0 +lat_0=90
>> +lat_ts=71
>>  +ellps=WGS84 +datum=WGS84
>> -121.33955 39.1012523
>> -2544346.32     -5373003.77
>
> Andrea,
>
> I think this is related to the recently reported problem in:
>
>  http://bugzilla.remotesensing.org/show_bug.cgi?id=1558
>
> Hopefully I'll be able to resolve it though for your purposes I guess
> you should just ignore the windows proj.4 results for now.
>
> 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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-- 
Bruce Raup
http://cires.colorado.edu/~braup/