[Proj] Geo Transfoms and calculations
Gerald I. Evenden
geraldi.evenden at gmail.com
Tue Dec 30 13:24:05 EST 2008
On Tuesday 30 December 2008 12:39:57 pm Eric Miller wrote:
> You need only a minor modification to Gerald's libproj4 to compile on
> windows. Because Microsoft is lame, their math library does not include
> atanh (or asinh or acosh).
That's incredible! H&S indicate these are C99 so that may be part of the
reason. But still ... it is almost 09. It just shows that nobody in Redmond
got beyond 4th grade math ... oops, arithmatic.
> Previously, I overcame this by building in a naive implementation of
> atanh as:
> double atanh( double x )
> return log((1 + x)/(1 - x))/2;
> Since Gerald has since embraced the GSL, maybe we can get him to use
> the GSL versions of those functions and let the GNU folks handle
> platform compatibility.
I use MIT which is apparently tolerated by GSL but I don't want to get into
that can of ugly worms. Besides, I do not have the libm source anyway.
Kinda brings up a point: isn't gcc and library under GSL so that nobody can
distribute a binary that uses the library without the associated BS?
All of the equivalent forms, like above, ought to be available in math
references on the Internet (just google 'atanh') or in Abramowitz(sp.).
Put the code into gatesmath.c and gatesmath.h and attach to the Makefile
lists. ;-) NO, NO! Don't answer that! No more discussion on this subject!
I'm sorry, but it is crap like that that makes me have such a loathesome
opinion of M$.
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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