[Proj] Lambert Conformal Conic

Irwin Scollar al001 at uni-koeln.de
Mon Apr 27 11:11:09 EST 2009

It's important to learn that some of the constants for Lambert 
Conformal Conic are not correct in various sources, but the intent of 
my posting was to ask those better versed in numerical matters on 
this list than I am, which of the methods for which I gave references 
give the most accurate results in those cases where I have no 
"official" formulae like I do in the case of France, but where I do 
have official values for the parallels of latitude, false Eastings 
and Northings and the ellipse.

For France, in order to get the same results within the limits of 
floating point accuracy, I must use the maths supplied by the IGN. 
However, for places where I've not found such official formulae, 
perhaps one of the other formulae in the references I cited  have the 
lowest average error out at the projection limits.

Irwin Scollar

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