[Rd] (PR#12770) format() under Windows giv wrong resuts with

[ripley at stats.ox.ac.uk]

On Wed, 10 Sep 2008, Bill Dunlap wrote:

> I can reproduce the problem on Windows XP service pack 3
> with R 2.8.0-dev if I set the locale to "italian" (by default
> it is English_United States" for me):
>   > pippo=strptime("23:43:12", format="%H:%M:%S")
>   > format(pippo, format="%I:%M:%S %p")
>   [1] "11:43:12 PM"
>   > Sys.setlocale(loc="italian")
>   [1] "LC_COLLATE=Italian_Italy.1252;LC_CTYPE=Italian_Italy.1252;LC_MONETARY=Italian_Italy.1252;LC_NUMERIC=C;LC_TIME=Italian_Italy.1252"
>   >  format(pippo, format="%I:%M:%S %p")
>   [1] "11:43:12 "
> It does look like a Windows problem.

Or a deliberate locale definition on Windows.  The R help does say

      Locale-specific conversions to and from character strings are used
      where appropriate and available.  This affects the names of the
      days and months, the AM/PM indicator (if used) and the separators
      in formats such as '%x' and '%X'.

and AFAICS none is used in the Italian locale on Windows XP.  (POSIX does 
not say that this is allowed to be empty, but it also does not say that it 
not allowed.)

>
> On Wed, 10 Sep 2008 ripley at stats.ox.ac.uk wrote:
>
>> On Windows XP SP3
>>
>>> format(pippo, format="%I:%M:%S %p")
>> [1] "11:43:12 PM"
>>
>> In any case, if there is a problem it is in Windows, not in R, since this
>> is an Windows service that is being called.  So there is no evidence at
>> all of any bug in R here.
>>
>> On Wed, 10 Sep 2008, pego.enrico at tiscali.it wrote:
>>
>>> Full_Name: Enrico Pegoraro
>>> Version: 2.7.2
>>> OS: Windows
>>> Submission from: (NULL) (87.4.187.101)
>>>
>>>
>>> The
>>> format(timevar,format="%I:%M:%S %p")
>>> instruction, with "timevar" a "POSIXt"  "POSIXlt" variable, give wrong return
>>> data.
>>> The format sentence string "%I:%M:%S %p" requires times with AM/PM indicator,
>>> but the resulting output doesn't contain it.
>>> Example:
>>>> pippo=strptime("23:43:12", format="%H:%M:%S")
>>>> pippo
>>> [1] "2008-09-10 23:43:12"
>>>> class(pippo)
>>> [1] "POSIXt"  "POSIXlt"
>>>> format(pippo, format="%I:%M:%S %p")
>>> [1] "11:43:12 "
>>>
>>> Note that in linux version of R format() works correctly.
>>> Best regards
>>> Enrico
>> ... signatures ...
>
> ----------------------------------------------------------------------------
> Bill Dunlap
> TIBCO Spotfire
> wdunlap tibco.com
>
> "All statements in this message represent the opinions of the author and do
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-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
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