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<TITLE>Projection WGS84 in decimal degree </TITLE>
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<P><FONT SIZE=2 FACE="Arial">Hi all,</FONT>
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<P><FONT SIZE=2 FACE="Arial">I have a set of WGS84 data points that come from GPS system in decimal degree</FONT> <FONT SIZE=2 FACE="Arial">longitude/latitude coordinates.</FONT>
<BR><FONT SIZE=2 FACE="Arial">I would like to display them with mapserver using a mapfile which already define several layers in Lambert II.</FONT>
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<P><FONT SIZE=2 FACE="Arial">I did specified the global projection in the mapfile for Lambert II etendu :</FONT>
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<P><FONT SIZE=2 FACE="Courier New">PROJECTION</FONT><BR>
<FONT SIZE=2 FACE="Courier New">"init=epsg:27582"</FONT><BR>
<FONT SIZE=2 FACE="Courier New">END</FONT><BR>
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<FONT SIZE=2 FACE="Arial">The GPS LAYER describing the WGS84 data includes the projection definition for the WGS84 :</FONT>
<BR><FONT SIZE=2 FACE="Courier New">LAYER<BR>
NAME "GPS"<BR>
PROJECTION<BR>
"init=epsg:4326"<BR>
END<BR>
...<BR>
END</FONT>
<BR><FONT SIZE=2 FACE="Arial">But points are not displayed at the right place (at about 200km far away) :-( </FONT>
<BR><FONT SIZE=2 FACE="Arial">Apparently, the 4326 epsg definition considers longitude/latitude coordinates in Degree/Minute/Second, while my data are in Decimal Degrees.</FONT><BR>
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<FONT SIZE=2 FACE="Arial">So I tried to specify the following in the GPS layer :<BR>
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<FONT SIZE=2 FACE="Courier New">PROJECTION</FONT><BR>
<FONT SIZE=2 FACE="Courier New">"proj=longlat"</FONT><BR>
<FONT SIZE=2 FACE="Courier New">"ellps=WGS84"</FONT><BR>
<FONT SIZE=2 FACE="Courier New">"datum=WGS84"</FONT><BR>
<FONT SIZE=2 FACE="Courier New">"units=dd"</FONT><BR>
<FONT SIZE=2 FACE="Courier New">END</FONT><BR>
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<FONT SIZE=2 FACE="Arial">but mapserver returns: "Error in msProcessProjection(): unknown unit conversion id" </FONT>
<BR><FONT SIZE=2 FACE="Arial">The prog -lu command doesn't list the "dd" unit...</FONT>
<BR><FONT SIZE=2 FACE="Arial">How to display longlat data in Decimal Degree under Mapserver?<BR>
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<FONT SIZE=2 FACE="Arial">Regards</FONT>
<BR><FONT SIZE=2 FACE="Arial">FP</FONT>
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