Topic: Why no shuffle_output in the proposed random number facility?
Author: petebecker@acm.org (Pete Becker)
Date: Fri, 7 Nov 2003 20:17:35 +0000 (UTC) Raw View
James Kuyper wrote:
>
> petebecker@acm.org (Pete Becker) wrote in message news:<3FA99CB4.C816BFC7@acm.org>...
> > Ian McCulloch wrote:
> > >
> > > I was just looking over the additions that have been accepted for the LTR.
> > > What immediately stuck out was in the random number library, the
> > > shuffle_output engine is in the list of engines "considered for inclusion,
> > > but left out for the following reasons:". But, in the case of
> > > shuffle_output, no reason is given. Indeed, the 'comments' section is only
> > > complementary: "compound engine that reorders the base engine's output,
> > > little overhead for generation (one multiplication)". It almost looks like
> > > it could be an editorial mistake that it was not in the previous table.
> > > Rationale please?
> > >
> >
> > There are many things that could have been included. Almost all of them
> > weren't.
>
> The question was "why?".
Yes, that is the question that I replied to. Listing reasons for not
including all the things that weren't included would be a tedious and
pointless task.
> Also, why is the reason (whatever it is)
> missing from the "comments" section?
>
If it really matters, ask the person who wrote the paper.
--
Pete Becker
Dinkumware, Ltd. (http://www.dinkumware.com)
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Author: eldiener@earthlink.net ("Edward Diener")
Date: Sat, 8 Nov 2003 00:27:32 +0000 (UTC) Raw View
Pete Becker wrote:
> James Kuyper wrote:
>>
>> petebecker@acm.org (Pete Becker) wrote in message
>> news:<3FA99CB4.C816BFC7@acm.org>...
>>> Ian McCulloch wrote:
>>>>
>>>> I was just looking over the additions that have been accepted for
>>>> the LTR. What immediately stuck out was in the random number
>>>> library, the shuffle_output engine is in the list of engines
>>>> "considered for inclusion, but left out for the following
>>>> reasons:". But, in the case of shuffle_output, no reason is
>>>> given. Indeed, the 'comments' section is only complementary:
>>>> "compound engine that reorders the base engine's output, little
>>>> overhead for generation (one multiplication)". It almost looks
>>>> like it could be an editorial mistake that it was not in the
>>>> previous table. Rationale please?
>>>>
>>>
>>> There are many things that could have been included. Almost all of
>>> them weren't.
>>
>> The question was "why?".
>
> Yes, that is the question that I replied to. Listing reasons for not
> including all the things that weren't included would be a tedious and
> pointless task.
No one asked for the reasons for not including everything which wasn't
included. Someone asked only for the reasons for not including
shuffle_output.
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Author: petebecker@acm.org (Pete Becker)
Date: Sat, 8 Nov 2003 02:58:54 +0000 (UTC) Raw View
Edward Diener wrote:
>
> Pete Becker wrote:
> > James Kuyper wrote:
> >>
> >> petebecker@acm.org (Pete Becker) wrote in message
> >> news:<3FA99CB4.C816BFC7@acm.org>...
> >>> Ian McCulloch wrote:
> >>>>
> >>>> I was just looking over the additions that have been accepted for
> >>>> the LTR. What immediately stuck out was in the random number
> >>>> library, the shuffle_output engine is in the list of engines
> >>>> "considered for inclusion, but left out for the following
> >>>> reasons:". But, in the case of shuffle_output, no reason is
> >>>> given. Indeed, the 'comments' section is only complementary:
> >>>> "compound engine that reorders the base engine's output, little
> >>>> overhead for generation (one multiplication)". It almost looks
> >>>> like it could be an editorial mistake that it was not in the
> >>>> previous table. Rationale please?
> >>>>
> >>>
> >>> There are many things that could have been included. Almost all of
> >>> them weren't.
> >>
> >> The question was "why?".
> >
> > Yes, that is the question that I replied to. Listing reasons for not
> > including all the things that weren't included would be a tedious and
> > pointless task.
>
> No one asked for the reasons for not including everything which wasn't
> included. Someone asked only for the reasons for not including
> shuffle_output.
>
Look it up in the list of things that weren't included. It's a rather
long list, and it doesn't give many reasons, but maybe you'll luck out.
--
Pete Becker
Dinkumware, Ltd. (http://www.dinkumware.com)
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Author: ianmcc@lorentz.leidenuniv.nl (Ian McCulloch)
Date: Wed, 5 Nov 2003 23:08:37 +0000 (UTC) Raw View
Hi,
I was just looking over the additions that have been accepted for the LTR.
What immediately stuck out was in the random number library, the
shuffle_output engine is in the list of engines "considered for inclusion,
but left out for the following reasons:". But, in the case of
shuffle_output, no reason is given. Indeed, the 'comments' section is only
complementary: "compound engine that reorders the base engine's output,
little overhead for generation (one multiplication)". It almost looks like
it could be an editorial mistake that it was not in the previous table.
Rationale please?
That aside, the most useful realization of this engine (at least for
monte-carlo) is the floating-point version: pick a table entry by
int(floor(R * Table.size())). Or is there some adaptor that would do this
automatically from the int version? And why not have the table size as a
parameter? The *extremely* paranoid might want to choose a table size that
is a prime, for example....
Algorithm "A" from Knuth might be another candidate for inclusion.
Cheers,
Ian McCulloch
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Author: petebecker@acm.org (Pete Becker)
Date: Thu, 6 Nov 2003 01:27:18 +0000 (UTC) Raw View
Ian McCulloch wrote:
>
> I was just looking over the additions that have been accepted for the LTR.
> What immediately stuck out was in the random number library, the
> shuffle_output engine is in the list of engines "considered for inclusion,
> but left out for the following reasons:". But, in the case of
> shuffle_output, no reason is given. Indeed, the 'comments' section is only
> complementary: "compound engine that reorders the base engine's output,
> little overhead for generation (one multiplication)". It almost looks like
> it could be an editorial mistake that it was not in the previous table.
> Rationale please?
>
There are many things that could have been included. Almost all of them
weren't.
--
Pete Becker
Dinkumware, Ltd. (http://www.dinkumware.com)
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Author: kuyper@wizard.net (James Kuyper)
Date: Fri, 7 Nov 2003 06:35:57 +0000 (UTC) Raw View
petebecker@acm.org (Pete Becker) wrote in message news:<3FA99CB4.C816BFC7@acm.org>...
> Ian McCulloch wrote:
> >
> > I was just looking over the additions that have been accepted for the LTR.
> > What immediately stuck out was in the random number library, the
> > shuffle_output engine is in the list of engines "considered for inclusion,
> > but left out for the following reasons:". But, in the case of
> > shuffle_output, no reason is given. Indeed, the 'comments' section is only
> > complementary: "compound engine that reorders the base engine's output,
> > little overhead for generation (one multiplication)". It almost looks like
> > it could be an editorial mistake that it was not in the previous table.
> > Rationale please?
> >
>
> There are many things that could have been included. Almost all of them
> weren't.
The question was "why?". Also, why is the reason (whatever it is)
missing from the "comments" section?
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