Subject: Re: [boost] New numeric data type proposal
From: Marc Glisse (marc.glisse_at_[hidden])
Date: 2014-03-26 02:37:13
On Tue, 25 Mar 2014, John Maddock wrote:
> Thanks for the explanation, it's interesting, and almost the same as "exact
> floating point" types which are represented as a/b x 2^n and have exact
> (arbitrary precision) operations for everything except division (which is
> unsupported).
I think you mean a*2^n. There are LGPL implementations in CGAL: Gmpzf,
MP_Float and most recently Mpzf.
With a/b*2^n (I wanted to try it as well, but I didn't have time to
implement it), I don't see any reason not to support division.
It still seems quite a bit different from what Damian was suggesting.
Performance is the main driver for those weird types ("usual" rationals
would work), and a different performance profile will fit completely
different applications.
-- Marc Glisse