Subject: Re: [boost] [fixed_point] Request for interest in a binary fixed point library
From: Vicente J. Botet Escriba (vicente.botet_at_[hidden])
Date: 2012-04-10 16:55:35
Le 10/04/12 19:46, Andrii Sydorchuk a écrit :
>> the recent discussion on the MultiplePrecission Arithmetic library has
>> show that some people has its ow fixed point library.
> Could you explain a bit your idea? By fixed point library do you mean fixed
> floating-point types (e.g. 1024-bit double)?
No. I meant really a fixed, not a floating -point, in which the
fractional part is fixed not variable. C++/Boost Chrono is designed in
some way as a fixed point time unit, limited to the use of intmax_t
type as underlying (which is enough to represent the time we want to
represent). My current needs are for small fixed-point, not for
arbitrary large fixed-point numbers, so I'll need less than word-bits
You can take a look at
http://en.wikipedia.org/wiki/Fixed-point_arithmetic. This will give you
the context. This C++ proposal
quite in line of the design I'm locking for.
The domain is quite related to the quantization (see
http://en.wikipedia.org/wiki/Quantization_%28signal_processing%29 for a
brief overview) where fixed-point is a way of uniform quantization. For
the applications I'm working on now, I will need also non-uniform
quantizations, as the ones provided by the reverse of a monotonic
function or lookup-tables, but this is out of the scope of a fixed-point
The questions on my initial post are some of the ones we need to answer
when designing such a library.
Hope this clarifies the intent,
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