[Proj] NTv2 info

Gerald I. Evenden geraldi.evenden at gmail.com
Tue Jun 2 12:57:51 EST 2009

Kudos to the Swiss---so far they are the only ones that seem to have format 
information on the NTv2 correction files.

A slap on the face with cold, wet noodles to the Canadians because I cannot 
locate any format details on the Canadian NTv2 distribution file.  The only 
thing I can find is the documenation of a program to access the file, which 
deserves another slap for not being available in source form.

I seem to get the idea that the Canadians developed this format---comments 
please---and if they did then the designers deserve to be flogged for 8 days 
with wet noodles for "positive east longitude."  I can't believe it!!!!  What 
is unbelievable arrogance by whoever had that stupid---yes, *VERY* 
stupid---idea.  I was looking at the headers of a Swiss NTv2 file and sure 
enough, negative values for longitude.  What's in that Molson anyway?  The 
McKenzie brothers must have been co-chairing the development commitee.

An intersting aside demonstrated by the Swiss distribution: the compress ASCII 
version of the NTv2 file is slightly smaller than the binary version.  
Wouldn't it have been nice if the McKenzie brothers looked into this when 
spec'ing the output form and saved everyone from the curse of determining 
endian conversion?

There is a problem with the Swiss documentation: it is in German and the 
details of the data records is not as clear as the headers.

Obviously, I have not exhausted all possible 4,000 google hits in looking for 
documentation.  If someone is aware of a defining english pdf somewhere, 
please let me know.  Thanks.

The whole religious complexion of the modern world is due
to the absence from Jerusalem of a lunatic asylum.
-- Havelock Ellis (1859-1939) British psychologist

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