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<DIV dir=ltr align=left><SPAN class=108273209-07102008></SPAN><SPAN
class=108273209-07102008><FONT face=Arial>There is a picture of the Sud Algerie
Grid on page 4-25 in</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=108273209-07102008><FONT
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=108273209-07102008><FONT face=Arial><A
href="http://www1.nga.mil/ProductsServices/GeodesyGeophysics/WorldGeodeticSystem/Related%20Documents/8358_1a.pdf">http://www1.nga.mil/ProductsServices/GeodesyGeophysics/WorldGeodeticSystem/Related%20Documents/8358_1a.pdf</A></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=108273209-07102008><FONT
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=108273209-07102008><FONT face=Arial>but the
resolution is bad. One can see that the grid extends farther
south than the zero Northing line, though. </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=108273209-07102008><FONT
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=108273209-07102008><FONT face=Arial>I wrote:
</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=108273209-07102008><FONT
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=108273209-07102008><FONT face=Arial>>
<SPAN class=262514013-06102008><FONT face=Arial>Let me see if I got it
right.</FONT></SPAN></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=108273209-07102008><FONT face=Arial><SPAN
class=262514013-06102008></SPAN></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=108273209-07102008><FONT face=Arial><SPAN
class=262514013-06102008>but I didn't; the wrap-around occurs where the
Northing becomes zero. </SPAN></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=108273209-07102008><FONT face=Arial><SPAN
class=262514013-06102008></SPAN></FONT></SPAN><SPAN
class=262514013-06102008><SPAN class=108273209-07102008><FONT
face=Arial>Clifford Mugnier wrote (to me): </FONT></SPAN></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=262514013-06102008><SPAN
class=108273209-07102008><FONT face=Arial></FONT></SPAN></SPAN> </DIV>
<DIV dir=ltr align=left>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> Clifford J Mugnier [mailto:cjmce@lsu.edu]
<BR><B>Sent:</B> den 6 oktober 2008 16:13<BR><B>To:</B> Mikael
Rittri<BR><B>Subject:</B> RE: [Proj] Terminology for
origins<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV id=idOWAReplyText12980 dir=ltr>
<DIV dir=ltr><FONT face="Times New Roman" size=2>No. From the Northing
being 300 km at the Latitude of Origin, 33<SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: 'Times New Roman','serif'">º<SPAN> 18</SPAN>'
North, going South from there the ordinate would decrease to zero. At that
point, it would then have a "jump" value of 1,000 km and then decrease South
from there. Such things require a logical "IF" to work properly in GIS
software. With most of GIS software being programmed by
programmers and not Cartographers or Geodesists, it remains a
conundrum.</SPAN></FONT></DIV>
<DIV dir=ltr><FONT face="Times New Roman" size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: 'Times New Roman','serif'"></SPAN></FONT> </DIV>
<DIV dir=ltr><FONT face="Times New Roman" size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: 'Times New Roman','serif'">Likewise, using
ellipsoidal Loxodromes for boundaries between various Grids ...
:-)</SPAN></FONT></DIV>
<DIV dir=ltr><FONT face="Times New Roman" size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: 'Times New Roman','serif'"></SPAN></FONT> </DIV>
<DIV dir=ltr><FONT face="Times New Roman" size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: 'Times New Roman','serif'">C.
Mugnier</SPAN></FONT></DIV></DIV>
<DIV dir=ltr><BR>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> Mikael Rittri
[mailto:Mikael.Rittri@carmenta.com]<BR><B>Sent:</B> Mon 06-Oct-08
09:05<BR><B>To:</B> Clifford J Mugnier; PROJ.4 and general Projections
Discussions<BR><B>Subject:</B> RE: [Proj] Terminology for
origins<BR></FONT><BR></DIV>
<DIV dir=ltr>
<DIV dir=ltr align=left><SPAN class=262514013-06102008><FONT face=Arial>Thanks
for explaining. I did not understand that the extra False
Northing should be added only south of the False
Origin. </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=262514013-06102008><FONT face=Arial>Let me
see if I got it right.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=262514013-06102008><FONT
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=262514013-06102008><SPAN
class=108273209-07102008><FONT face=Arial>[ the rest of my post can be
found at <A
href="http://lists.maptools.org/pipermail/proj/2008-October/003876.html">http://lists.maptools.org/pipermail/proj/2008-October/003876.html</A> ]
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