[Proj] Discovery: libproj4 stmerc = French Gauss-Laborde

Gerald I. Evenden gerald.evenden at verizon.net
Sun Jun 18 21:28:13 EDT 2006

The French Transverse Mercator (NT/G 76 publication) is now in libproj4 on my 
desk---+proj=ftmerc .  It extends well beyond the 5 degree limit of tmerc but 
starts to fail with low latitudes and extended longitudes beyond 40 degrees.  
It compares with the German online site within +-0.2mm.  Unfortunately the 
German site does not display major axis and ellipsoid parameters so it is 
possible that errors in this range are due to minor variations of these 
figures and/or how they are specified.

ftmerc has forward and inverse mode.

This release of libproj4 will not be on my web site until the documentation is 
brought up to date and the new output formating routine is installed.

If anyone wants a prelim copy of proj_ftmerc.c and proj_psi.c, I can email 
these files.

I am not going to do anything at the moment with the Dozier method.

Jerry and the low-riders: Daisy Mae and Joshua
"Cogito cogito ergo cogito sum"
   Ambrose Bierce, The Devil's Dictionary

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