[Rd] [External] Re: rpois(9, 1e10)

[Avraham Adler]

Fantastic!!

Thanks,

Avi

On Wed, Jan 22, 2020 at 11:14 AM Spencer Graves <spencer.graves using prodsyse.com>
wrote:

>
>
> On 2020-01-22 02:54, Martin Maechler wrote:
> >>>>>> Martin Maechler
> >>>>>>      on Tue, 21 Jan 2020 09:25:19 +0100 writes:
> >>>>>> Ben Bolker
> >>>>>>      on Mon, 20 Jan 2020 12:54:52 -0500 writes:
> >      >> Ugh, sounds like competing priorities.
> >
> >      > indeed.
> >
> >      >> * maintain type consistency
> >      >> * minimize storage (= current version, since 3.0.0)
> >      >> * maximize utility for large lambda (= proposed change)
> >      >> * keep user interface, and code, simple (e.g., it would be easy
> enough
> >      >> to add a switch that provided user control of int vs double
> return value)
> >      >> * backward compatibility
> >
> >      > Last night, it came to my mind that we should do what we have
> >      > been doing in quite a few places in R, the last couple of years:
> >
> >      > Return integer when possible, and switch to return double when
> >      > integers don't fit.
> >
> >      > We've been doing so even for  1:N  (well, now with additional
> ALTREP wrapper),
> >      > seq(), and even the fundamental  length()  function.
> >
> >      > So I sat down and implemented it .. and it seemed to work
> >      > perfectly:  Returning the same random numbers as now, but
> >      > switching to use double (instead of returning NAs) when the
> >      > values are too large.
> >
> >      > I'll probably commit that to R-devel quite soonish.
> >      > Martin
> >
> > Committed in svn rev 77690; this is really very advantageous, as
> > in some cases / applications or even just limit cases, you'd
> > easily get into overflow sitations.
> >
> > The new R 4.0.0 behavior is IMO  "the best of" being memory
> > efficient (integer storage) in most cases (back compatible to R 3.x.x)
> and
> > returning desired random numbers in large cases (compatible to R <=
> 2.x.x).
> >
> > Martin
>
>
> Wunderbar!  Sehr gut gemacht!  ("Wonderful!  Very well done!") Thanks,
> Spencer
> >
> >      >> On 2020-01-20 12:33 p.m., Martin Maechler wrote:
> >      >>>>>>>> Benjamin Tyner
> >      >>>>>>>> on Mon, 20 Jan 2020 08:10:49 -0500 writes:
> >      >>>
> >      >>> > On 1/20/20 4:26 AM, Martin Maechler wrote:
> >      >>> >> Coming late here -- after enjoying a proper weekend ;-) --
> >      >>> >> I have been agreeing (with Spencer, IIUC) on this for a long
> >      >>> >> time (~ 3 yrs, or more?), namely that I've come to see it as
> a
> >      >>> >> "design bug" that  rpois() {and similar} must return return
> typeof() "integer".
> >      >>> >>
> >      >>> >> More strongly, I'm actually pretty convinced they should
> return
> >      >>> >> (integer-valued) double instead of NA_integer_   and for that
> >      >>> >> reason should always return double:
> >      >>> >> Even if we have (hopefully) a native 64bit integer in R,
> >      >>> >> 2^64 is still teeny tiny compared .Machine$double.max
> >      >>> >>
> >      >>> >> (and then maybe we'd have .Machine$longdouble.max  which
> would
> >      >>> >> be considerably larger than double.max unless on Windows,
> where
> >      >>> >> the wise men at Microsoft decided to keep their workload
> simple
> >      >>> >> by defining "long double := double" - as 'long double'
> >      >>> >> unfortunately is not well defined by C standards)
> >      >>> >>
> >      >>> >> Martin
> >      >>> >>
> >      >>> > Martin if you are in favor, then certainly no objection from
> me! ;-)
> >      >>>
> >      >>> > So now what about other discrete distributions e.g. could a
> similar
> >      >>> > enhancement apply here?
> >      >>>
> >      >>>
> >      >>> >> rgeom(10L, 1e-10)
> >      >>> >  [1]         NA 1503061294         NA         NA
> 1122447583         NA
> >      >>> >  [7]         NA         NA         NA         NA
> >      >>> > Warning message:
> >      >>> > In rgeom(10L, 1e-10) : NAs produced
> >      >>>
> >      >>> yes, of course there are several such distributions.
> >      >>>
> >      >>> It's really something that should be discussed (possibly not
> >      >>> here, .. but then I've started it here ...).
> >      >>>
> >      >>> The  NEWS  for R 3.0.0 contain (in NEW FEATURES) :
> >      >>>
> >      >>> * Functions rbinom(), rgeom(), rhyper(), rpois(), rnbinom(),
> >      >>> rsignrank() and rwilcox() now return integer (not double)
> >      >>> vectors.  This halves the storage requirements for large
> >      >>> simulations.
> >      >>>
> >      >>> and what I've been suggesting is to revert this change
> >      >>> (svn rev r60225-6) which was purposefully and diligently done by
> >      >>> a fellow R core member, so indeed must be debatable.
> >      >>>
> >      >>> Martin
> >      >>>
> >      >>> ______________________________________________
> >      >>> R-devel using r-project.org mailing list
> >      >>> https://stat.ethz.ch/mailman/listinfo/r-devel
> >      >>>
> >
> >      >> ______________________________________________
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> >
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> >
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