[Fwd: longitude problem]

[Thomas LOUBRIEU <thomas.loubrieu@xxxxxxxxxx>]

Hi again,

It's now working, I have commented these lines in Ferret.pl :

sub fixLongitude {
    # Ferret has problems with longitudes < 0
    my ($xlo, $xhi) = @_;
# test TL
#    if ($xlo ne "" && $xlo < 0){
#	$xlo += 360;
#	if ($xhi ne ""){
#	    $xhi += 360;
#	}
#    }
#    if ($xhi ne "" && $xhi < 0){
#	$xhi += 360.;
#    }
    return ($xlo, $xhi);
}


I will now check Ferret references...
However Ferret has a "translation" bug when I set a region this way :

set region/x="320":"330"/y="20.0":"62.0"/k=1/l=1

But Ferret is working when I do :

set region/x="-40":"-30"/y="20.0":"62.0"/k=1/l=1

I use Ferret 4.51 for linux, perhaps there has been a change in
longitudes convention.

Bye,

Thomas.

--- Begin Message ---

• To: las_users@xxxxxxxxxxxxxxxxxxx
• Subject: longitude problem
• From: Thomas LOUBRIEU <thomas.loubrieu@xxxxxxxxxx>
• Date: Thu, 14 Nov 2002 11:04:42 +0100
• Organization: ifremer

Hi,

I use LAS 6.0

I have included a COARDS netcdf dataset through the perl script :

../xml/perl/addXml.pl las.xml las.xml <my netcdf file>
../xml/perl/genLas.pl las.xml 


My netcdf file is covering longitudes from -40 to 0 degrees east with a
measurement every 2 degrees.
In my las.xml file I have a longitude axis :
 
<EPPE_WAM_Atl_200203200300_nc_lon units="degrees_east" type="x">
  <arange start="-40" step="2" size="21"/>
</EPPE_WAM_Atl_200203200300_nc_lon>

On the LAS User Interface my plotted grid appears with :
	las_longitude = -40 + (real_longitude -22) mod 40

Thus, if I plot the full region, the frame is well located but the
top-left corner of my grid is located at longitude -22E instead of -40E.
The top-right corner is located at longitude -22E instead of 0 and every
points in my grid are translated as well.

The same thing happens if my longitude axis is (changing "start"
attribute to "320" and re-launching "../xml/perl/genLas.pl las.xml"):
<EPPE_WAM_Atl_200203200300_nc_lon units="degrees_east" type="x">
  <arange start="320" step="2" size="21"/>
</EPPE_WAM_Atl_200203200300_nc_lon>

Do someone have an idea of what happens to my netcdf file.

Thanks,

Thomas.

--- End Message ---