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Subject: [Boost-announce] [boost] [review] Multiprecision review (June 8th - 17th, 2012)
From: Jeffrey Lee Hellrung, Jr. (jeffrey.hellrung_at_[hidden])
Date: 2012-06-08 10:28:09

Okay, it's that time. Apologies for not sending a reminder, but there had
been a lot of pre-review comments over the last week or so, so I think this
has been on at least some people's radar. The original review announcement
is given below.

On Tue, May 29, 2012 at 2:08 PM, Jeffrey Lee Hellrung, Jr. <
jeffrey.hellrung_at_[hidden]> wrote:

> Hi all,
> The review of the proposed Boost.Multiprecision library authored by John
> Maddock and Christopher Kormanyos has been scheduled for
> June 8th - June 17th, 2012
> and will be managed by myself.
> From the Introduction:
> --------
> "The Multiprecision Library provides *User-defined* integer, rational and
> floating-point C++ types which try to emulate as closely as practicable the
> C++ built-in types, but provide for more range and precision. Depending
> upon the number type, precision may be arbitrarily large (limited only by
> available memory), fixed at compile time values, for example 50 decimal
> digits, or a variable controlled at run-time by member functions. The types
> are expression-template-enabled for better performance than naive
> user-defined types."
> --------
> And from the original formal review request from John:
> --------
> Features:
> * Expression template enabled front end.
> * Support for Integer, Rational and Floating Point types.
> Supported Integer backends:
> * GMP.
> * Libtommath.
> * cpp_int.
> cpp_int is an all C++ Boost licensed backend, supports both arbitrary
> precision types (with Allocator support), and signed and unsigned fixed
> precision types (with no memory allocation).
> There are also some integer specific functions - for Miller Rabin testing,
> bit fiddling, random numbers. Plus interoperability with Boost.Rational
> (though that loses the expression template frontend).
> Supported Rational Backends:
> * GMP
> * libtommath
> * cpp_int (as above)
> Supported Floating point backends:
> * GMP
> * MPFR
> * cpp_dec_float
> cpp_dec_float is an all C++ Boost licensed type, adapted from Christopher
> Kormanyos' e_float code (published in TOMS last year).
> All the floating point types, have full std lib support (cos sin exp, pow
> etc), as well as full interoperability with Boost.Math.
> There's nothing in principal to prevent extension to complex numbers and
> interval arithmetic types (plus any other number types I've forgotten!),
> but I've run out of energy for now ;-)
> Code is in the sandbox under /big_number/.
> Docs can be viewed online here:
> --------

Any review discussion should take place on the developers' list (
boost_at_[hidden]), and anyone may submit a formal review, either
publicly to the entire list or privately to just myself.

As usual, please consider the following questions in your formal review:

    What is your evaluation of the design?
    What is your evaluation of the implementation?
    What is your evaluation of the documentation?
    What is your evaluation of the potential usefulness of the library?
    Did you try to use the library? With what compiler? Did you have any
    How much effort did you put into your evaluation? A glance? A quick
reading? In-depth study?
    Are you knowledgeable about the problem domain?

And, most importantly, please explicitly answer the following question:

    Do you think the library should be accepted as a Boost library?

Lastly, please consider that John and Christopher have compiled a TODO list
[1] based on pre-review comments. Feel free to comment on the priority and
necessity of such TODO items, and whether any might be show-stoppers or
warrant conditional acceptance of the library.

Thanks in advance; looking forward to the discussion!

- Jeff (& John & Christopher)


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