Boost logo

Boost :

Subject: Re: [boost] [Review Request] Multiprecision Arithmetic Library
From: Andrii Sydorchuk (sydorchuk.andriy_at_[hidden])
Date: 2012-04-01 18:52:33

Hi John,

Nice work! It is a great first step for Boost on having its own
multiprecision library.

* libtommath

Is this library really required? From your benchmarks I see that cpp_int
type you've implemented is much better on almost all tests.

* Support for Integer, Rational and Floating Point types.

Are integer and floating-point types interconnected within the library?
Wouldn't it be better to come up with two separate libraries?

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).

I would like to clarify following question (didn't notice this in docs).
Let's say I want to create cpp_int fixed type to handle 129 bit signed
integer (1 bit for a sign and 128 to represent the value itself). Am I fine
with cpp_int_backend<128, true, void>? What is the size of cpp_int_backend<
128, true, void> structure? Does the unary minus operator overflows for the
smallest possible fixed integer value?

All the floating point types, have full std lib support (cos sin exp, pow
> etc), as well as full interoperability with Boost.Math.

What is the precision of the following operations: *, /, +, -, sqrt
for the cpp_dec_float
type? What is the memory usage? Any limitations on the maximum/minimum
value of exponent?

Andrii Sydorchuk

Unsubscribe & other changes:**

Boost list run by bdawes at, gregod at, cpdaniel at, john at