Re: [boost] Is there interest in e_float:Multiple-precisionfloatand special functions?

Subject: Re: [boost] Is there interest in e_float:Multiple-precisionfloatand special functions?
From: Lars Viklund (zao_at_[hidden])
Date: 2011-06-23 18:10:56

On Thu, Jun 23, 2011 at 09:45:11PM +0100, Christopher Kormanyos wrote:
> Jeff,
> 
> The original e_float publication in the ACM included a wide variety of the special functions of pure and applied mathematics
> extended to large parameter ranges. When preparing this original research work, I restricted the digit range to 300 in order to
> guarantee full precision of all special function calculations within known digit and parameter ranges.
> 
> In the future, it will be possible to extend e_float's digit range. In fact, the digit range can be extended any time when
> using e_float with its GMP and MPFR back ends. Simple mathematics like add, sub, mul, div, sqrt, etc. work for
> GMP and MPFR in very high digit ranges. However, constants like pi, log(2), Euler's gamma, etc. as well as
> e_float's special functions are not yet designed for these regions and not tested therein.
> 
> Also be aware that my portable big-number back-end included in e_float (called EFX) only includes order-N^2 multiplication.
> As such it can not be extended beyond several hundred digits. I can add Karatsuba and FFT multiplication to the EFX version
> at a later time, as I do have these methods in other programs.
> 
> With e_float, we are making a modest first step in big-number floats for boost at this time. We need to concentrate on the
> architecture and design of the program and the proper semantics of the floats. Digit extension is of secondary concern right now.
> 
> 
> Sincerely, Chris.
> 
> 
> 
> ________________________________
> From: "Jeffrey Lee Hellrung, Jr." <jeffrey.hellrung_at_[hidden]>
> To: boost_at_[hidden]
> Sent: Thursday, June 23, 2011 8:23 PM
> Subject: Re: [boost] Is there interest in e_float:Multiple-precisionfloatand special functions?
> 
> On Thu, Jun 23, 2011 at 8:33 AM, Christopher Kormanyos <e_float_at_[hidden]>wrote:
> [...]
> 
> > Remember, e_float in its present form only goes up to 300 digits.
> 
> [...]
> 
> I'm curious, what are the reasons for this limitation?  I may have missed
> this in previous discussion...

This sounds like awesome work, but note that list policy discourages
top-posting, instead preferring replies in-line or below.

-- 
Lars Viklund | zao_at_[hidden]