>>>>> Gabriel Becker
>>>>> on Mon, 14 Dec 2020 13:23:00 -0800 writes:
> Hi Edgar, I certainly don't think quantile(x, .975) should
> return 980, as that is a completely wrong answer.
> I do agree that it seems like the name is a bit
> offputting. I'm not sure how deep in the machinery you'd
> have to go to get digits to no effect on the names (I
> don't have time to dig in right this second).
> On the other hand, though, if we're going to make the
> names not respect digits entirely, what do we do when
> someone does quantile(x, 1/3)? That'd be a bad time had by
> all without digits coming to the rescue, i think.
> Best, ~G
and now we read more replies on this topic without anyone looking at
the pure R source code which is pretty simple and easy.
Instead, people do experiments and take time to muse about their findings..
Honestly, I'm disappointed: I've always thought that if you
*write* on R-devel, you should be able to figure out a few
things yourself before that..
It's not rocket science to see/know that you need to quickly look at
the quantile.default() method function and then to note
that it's format_perc(.) which is used to create the names.
Almost surely, I've been a bit envolved in creating parts of
this and probably am responsible for the current default
behavior.
....
....(sounds of digging) ...
....
....
....
....
....
....
--> Yes:
------------------------------------------------------------------------
r837 | maechler | 1998-03-05 12:20:37 +0100 (Thu, 05. Mar 1998) | 2 Zeilen
Ge?nderte Pfade:
M /trunk/src/library/base/R/quantile
M /trunk/src/library/base/man/quantile.Rd
fixed names(.) construction
------------------------------------------------------------------------
With this diff (my 'svn-diffB -c837 quantile') :
Index: quantile
==================================================================21c21,23
< names(qs) <- paste(round(100 * probs), "%", sep =
"")
---> names(qs) <- paste(formatC(100 * probs, format= "fg", wid=1,
> dig= max(2,.Options$digits)),
> "%", sep = "")
-----------------------------------------------------------------
so this was before this was modularized into the format_perc()
utility and quite a while before R 1.0.0 ....
Now, 22.8 years later, I do think that indeed it was not
necessarily the best idea to make the names() construction depend on the
'digits' option entirely and just protect it by using at least 2 digits.
What I think is better is to
1) provide an optional argument 'digits = 7'
back compatible w/ default getOption("digits")
2) when used, check that it is at least '1'
But then some scripts / examples of some people *will* change
..., e.g., because they preferred to have a global setting of digits=5
so I'm guessing it may make more people unhappy than other
people happy if we change this now, after close to 23 years .. ??
Martin
--
Martin Maechler
ETH Zurich and R Core team
> On Mon, Dec 14, 2020 at 11:55 AM Merkle, Edgar
> C. <merklee at missouri.edu> wrote:
>> All,
>>
>> Consider the code below
>>
>> options(digits=2)
>> x <- 1:1000
>> quantile(x, .975)
>> The value returned is 975 (the 97.5th percentile), but
>> the name has been shortened to "98%" due to the digits
>> option. Is this intended? I would have expected the name
>> to also be "97.5%" here. Alternatively, the returned
>> value might be 980 in order to match the name of "98%".
>>
>> Best, Ed
>>