From: Marc Glisse <marc.glisse@inria.fr>
To: Oliver Kullmann <o.kullmann@swansea.ac.uk>
Cc: gcc-help@gcc.gnu.org
Subject: Re: where are the implementations for <random>?
Date: Sun, 09 Apr 2017 18:24:00 -0000 [thread overview]
Message-ID: <alpine.DEB.2.20.1704092015110.1870@stedding.saclay.inria.fr> (raw)
In-Reply-To: <20170409173101.GA10474@csltok.swansea.ac.uk>
On Sun, 9 Apr 2017, Oliver Kullmann wrote:
> Hello,
>
> I thought that with the facilities from <random> we had good and
> well-defined ones -- but alas, only recently I realised that only say
> the Mersenne twister is well-defined in the standard, but roughly
> everything else is up to the implementer.
>
> Since reproducibility is crucial for us (as with most scientific
> applications), thus we need to implement ourselves the algorithms for
>
> 1. std::seed_seq
> 2. std::uniform_int_distribution
> 3. std::bernoulli_distribution (only for default p=0.5).
>
> Easiest would be to copy (and specialise) the gcc-implementations.
> I searched for it in the source-code, but couldn't find it:
>
> Where do I find the implementations for <random> ?
Option 1)
First you find the file called "random" (/usr/include/c++/6/random here),
then you notice that it contains
#include <bits/random.h>
#include <bits/opt_random.h>
#include <bits/random.tcc>
so you look for those files (and recursively if needed)
Option 2)
You compile a file that contains #include <random> using the -E flag, and
look for bernoulli_distribution or whatever in the output.
Option 3)
Get the sources for gcc.
grep -r bernoulli_distribution /the/sources
They all point to bits/random.h (with one function implemented in
bits/random.tcc), with older versions in tr1/.
--
Marc Glisse
next prev parent reply other threads:[~2017-04-09 18:24 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-09 17:31 Oliver Kullmann
2017-04-09 18:24 ` Marc Glisse [this message]
2017-04-09 23:32 ` Martin Sebor
2017-04-11 13:03 ` Oliver Kullmann
2017-04-11 18:26 ` Oliver Kullmann
2017-04-11 20:17 ` Oliver Kullmann
2017-04-11 20:27 ` Jonathan Wakely
2017-04-12 3:41 ` Oliver Kullmann
2017-04-12 5:01 ` Oliver Kullmann
2018-12-21 12:34 ` wrong sha512 values for 7.4.0 ? Oliver Kullmann
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