Hello James and Jon!
On Sat, Apr 9, 2011 at 10:58 PM, James K Beard <[email protected]> wrote:
> JonY - well, mine is in Fortran 95 structured format, with layers of classes
> and derived data types. An experienced programmer could port it to C++
> fairly quickly, giving you a a C++ class with overloaded arithmetic and
> casting/data conversion operations. But I'm not a C++ programmer and don't
> want to become one; I'm not in software or computer science and have other
> plans for my time than gaining expertise in C++. But I would be happy to
> support other people to do the conversion to C++.
>
> The Numerical Recopies core utilities are extended-precision fixed-point
> arithmetic without extensions (I do the extensions myself), an algorithm to
> compute pi to arbitrary precision, and an algorithm to do multiplication
> using an FFT to convolve polynomials of integers that are the extended
> precision mantissas broken up into bytes. The multiplication and division
> algorithms are non-trivial and the computer science in them is very much key
> to acceptable speeds in multiplication. If you guys are at all serious
> about this I will approach the NR people about how to proceed. My tentative
> thinking has been to put out what I have under the GPL, MIT, BSD or whatever
> license and note the NR modules needed to complete the package and leave it
> at that. For something to become a package in another language, I need a
> release into the MIT or BSD license. That's not at all very different from
> what they offer in the books and CD, so I think that it might be
> forthcoming, particularly if a plug for NR is included, but at this late
> date even that might not be required.
> ...
About Numerical Recipes -- they use a pretty restrictive license.
See, for example, their web site:
http://www.nr.com/com/how-we-license.html
I can't speak for them as to whether they would release some part
of their code (e.g., the extended-precision module) under a more
open license that would work for mingw-w64, but I expect that getting
their license relaxed would be an uphill battle.
One more comment about Numerical Recipes: I've never used
their extended-precision code, and James has battle-tested it,
so it's probably quite good, but in general, there are a lot pitfalls
in the Numerical Recipes algorithms and code. In fact, it's rather
notorious in the numerical-analysis community.
One summary of community concerns can be found here, under
the title "Numerical Recipes -- not so good":
http://amath.colorado.edu/computing/Fortran/numrec.html
Just a heads-up...
Best.
K. Frank
> ...
> James K Beard
>
> -----Original Message-----
> From: Jon [mailto:[email protected]] On Behalf Of JonY
> Sent: Saturday, April 09, 2011 9:07 PM
> ...
> I've talked with Kai sometime ago about licensing, GPL and LGPL aren't
> practical for mingw-w64, if it were, I would have taken libdecnumber and
> libquadmath from gcc directly.
>
> He opted for a MIT or BSD type license so mingw-w64 could still be used to
> develop proprietary software.
> ...
------------------------------------------------------------------------------
Xperia(TM) PLAY
It's a major breakthrough. An authentic gaming
smartphone on the nation's most reliable network.
And it wants your games.
http://p.sf.net/sfu/verizon-sfdev
_______________________________________________
Mingw-w64-public mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/mingw-w64-public
