(OT): Conversion of 'Lambert projection' data to longditude/latitude?

BrowserUk has asked for the wisdom of the Perl Monks concerning the following question:

Does anyone know how to convert data projected using the Lambert projection coordinate system (specification follows) into straight Longditude/Latitude pairs (also based around the Clarke 1866 spheroid)?

Projection    LAMBERT    
Units    METERS    
Spheroid    CLARKE1866    
Parameters        
 1st standard parallel    70 0 0.000    
 2nd standard parallel    50 0 0.000    
 central meridian    110 0 0.00    
 latitude of projection's origin    0 0 0.000    
 false easting (meters)    0.00000    
 false northing (meters)    0.00000
[download]

To keep it on topic, Perl code to do this would be great, but references that explain the conversion process (in layman's terms!) would be good too.

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Comment on (OT): Conversion of 'Lambert projection' data to longditude/latitude? Download Code

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Re: (OT): Conversion of 'Lambert projection' data to longditude/latitude? by planetscape (Chancellor) on Oct 28, 2005 at 15:59 UTC
Java map projections of the world - by Henry Bottomley might be of interest. The page contains some explanatory text, including alternate terms for the "Lambert Projection", and some Java/Javascript code. I have also found The Geometry Junkyard to be an excellent source of knowledge and code examples for similar questions. Update: these links from MathWorld look promising too... Lambert Azimuthal Equal-Area Projection Lambert Conformal Conic Projection Lambert Cylindrical Equal-Area Projection HTH, planetscape	[reply]
Re: (OT): Conversion of 'Lambert projection' data to longditude/latitude? by fizbin (Chaplain) on Oct 28, 2005 at 16:20 UTC
I found this reference to be moderately readable, if you follow the strategy of reading the page quickly once to get an overview, skipping the bits that are hard to understand, and then again more slowly after some formerly undefined terms are made plain. It takes about 20 minutes, but afterwards you will know way more than you wanted to about the parameters necessary to specify a map's projection. Then, read the next page for the formulas that use those parameters. Note that at many points through the first page, they keep talking about projections of an "ellipsoid". On your first read through (when skimming) substitute the word "sphere" for "ellipsoid". Then, on your second read through, remember that the Earth is not in fact a perfect sphere and therefore you need to take into account the fact that it bulges slightly at the equator if you're going to be lining up maps with two slightly different coordinate systems. -- `@/=map{[/./g]}qw/.h_nJ Xapou cets krht ele_ r_ra/; map{y/X_/\n /;print}map{pop@$_}@/for@/` [download]	[reply] [d/l]
Re: (OT): Conversion of 'Lambert projection' data to longditude/latitude? by zentara (Cardinal) on Oct 28, 2005 at 19:22 UTC
I got some good hits at http://groups.google.com by searching for "convert lambert latitude". I'm not really a human, but I play one on earth. flash japh	[reply]