On Tue, Feb 3, 2015 at 12:58 AM, phil@highoctane.be <phil@highoctane.be> wrote:

On Mon, Feb 2, 2015 at 5:22 PM, Pierre CHANSON <chans.pierre@gmail.com> wrote:

Hi everyone,
I was wondering if there was a package to manipulate floats like the MPFR library in C...

One issue with MPFR is the licensing, which is GNU.

No, its LGPL (http://www.mpfr.org/).�� Now something I didn't know and just read, you can even statically link an LGPL library, as long as you provide��

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I wonder if Pharo couldn't get a special licence for embedding as "MPFR��has continuously been supported by the��INRIA...".

Pharo is now 32-bit and uses the floatplugin to do the actual fast math.

Pharo with the 64-bit system will be able to do better and the float plugin will have to be rewritten anyway.

But MPFR could be put into a plugin.

As far as I am concerned, I'd rather get something based on GMP (https://gmplib.org/) but we are there in GNU territory. Which is not what I want for commercial apps.

Why GMP? From the timings table it looks like GMP is missing trigonometric functions, and ��that MPFR is equally as fast as GMP.

cheers -ben

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This table:��http://www.mpfr.org/mpfr-current/timings.html is showing some LGPL licencing that may be easier to deal with. But for sure, none of that is MIT :-(

Phil

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Then I found in http://stephane.ducasse.free.fr/Web/Draft/Float.pdf that using ScaledDecimal allows exact arithmetics. So I guess ScaledDecimal is the best class to use for playing with 20 decimals numbers ? :)

Thanks !

Pierre