On 6/22/2011 3:34 PM, Brian Diggs wrote: > On 6/22/2011 12:09 PM, Luke Miller wrote: >> For what it's worth, I cannot reproduce this problem under a nearly >> identical instance of R (R 2.12.1, Win 7 Pro 64-bit). I also can't >> reproduce the problem with R 2.13.0. You've got something truly weird >> going on with your particular instance of R. >> >> >>> is.na(strptime("5/3/1992", format="%m/%d/%Y")) >> [1] FALSE >>> is.na(strptime("5/2/1992", format="%m/%d/%Y")) >> [1] FALSE >>> sessionInfo() >> R version 2.12.1 (2010-12-16) >> Platform: i386-pc-mingw32/i386 (32-bit) >> >> locale: >> [1] LC_COLLATE=English_United States.1252 >> [2] LC_CTYPE=English_United States.1252 >> [3] LC_MONETARY=English_United States.1252 >> [4] LC_NUMERIC=C >> [5] LC_TIME=English_United States.1252 >> >> attached base packages: >> [1] stats graphics grDevices utils datasets methods base >> >> other attached packages: >> [1] rj_0.5.2-1 lattice_0.19-17 >> >> loaded via a namespace (and not attached): >> [1] grid_2.12.1 rJava_0.8-8 tools_2.12.1 > > Like Luke, I can not reproduce what you see in (an old installation of) > R 2.12.1 (and it also didn't have rj, lattice, grid, rJava, or tools > attached or loaded in any way). > > My vague gut feeling is it might be a timezone/daylight savings time > related issue (though usually times have to be involved). At least, > that is a common problem with weird things happening with dates. > > What do you get as output for the following? > > Sys.timezone() > Sys.info() > conflicts() > dput(strptime("5/3/1992", format="%m/%d/%Y")) > dput(as.POSIXct(strptime("5/3/1992", format="%m/%d/%Y"))) > dput(strptime("5/2/1992", format="%m/%d/%Y")) > dput(as.POSIXct(strptime("5/2/1992", format="%m/%d/%Y")))
> Sys.timezone() [1] "COT" > Sys.info() sysname release version nodename machine "Windows" "7 x64" "build 7601, Service Pack 1" "machine_name" "x86" login user "username" "username" > conflicts() [1] "untangle.specials" "body<-" "format.pval" "round.POSIXt" "trunc.POSIXt" "units" > dput(strptime("5/3/1992", format="%m/%d/%Y")) structure(list(sec = 0, min = 0L, hour = 0L, mday = 3L, mon = 4L, year = 92L, wday = 0L, yday = 123L, isdst = -1L), .Names = c("sec", "min", "hour", "mday", "mon", "year", "wday", "yday", "isdst" ), class = c("POSIXlt", "POSIXt")) > dput(as.POSIXct(strptime("5/3/1992", format="%m/%d/%Y"))) structure(NA_real_, class = c("POSIXct", "POSIXt"), tzone = "") > dput(strptime("5/2/1992", format="%m/%d/%Y")) structure(list(sec = 0, min = 0L, hour = 0L, mday = 2L, mon = 4L, year = 92L, wday = 6L, yday = 122L, isdst = 0L), .Names = c("sec", "min", "hour", "mday", "mon", "year", "wday", "yday", "isdst" ), class = c("POSIXlt", "POSIXt")) > dput(as.POSIXct(strptime("5/2/1992", format="%m/%d/%Y"))) structure(704782800, class = c("POSIXct", "POSIXt"), tzone = "") > > >> On Wed, Jun 22, 2011 at 2:40 PM, Alexander Shenkin<ashen...@ufl.edu> >> wrote: >>> On 6/22/2011 1:34 PM, Sarah Goslee wrote: >>>> On Wed, Jun 22, 2011 at 2:28 PM, David >>>> Winsemius<dwinsem...@comcast.net> wrote: >>>>> >>>>> On Jun 22, 2011, at 2:03 PM, Sarah Goslee wrote: >>>>> >>>>>> Hi, >>>>>> >>>>>> On Wed, Jun 22, 2011 at 11:40 AM, Alexander Shenkin<ashen...@ufl.edu> >>>>>> wrote: >>>>>>>> >>>>>>>> is.na(strptime("5/2/1992", format="%m/%d/%Y")) >>>>>>> >>>>>>> [1] FALSE >>>>>>>> >>>>>>>> is.na(strptime("5/3/1992", format="%m/%d/%Y")) >>>>>>> >>>>>>> [1] TRUE >>>>>> >>>>>> I can't reproduce your problem on R 2.13.0 on linux: >>>>> >>>>> I also cannot reproduce it on a Mac with 2.13.0 beta >>>> >>>> Which strongly suggests that you should start by upgrading your R >>>> installation if at all possible. >>>> >>>> I'd also recommend trying it on a default R session, with no extra >>>> packages loaded, and no items in your workspace. It's possible that >>>> something else is interfering. >>>> >>>> On linux, that's achieved by typing R --vanilla at the command line. >>>> I'm afraid I don't know how to do it for Windows, but should be >>>> similarly straightforward. >>>> >>> Thanks Sarah. Still getting the problem. I should surely upgrade, but >>> still, not a bad idea to get to the bottom of this, or at least have it >>> documented as a known issue. BTW, I'm on Windows 7 Pro x64. >>> >>> (running Rgui.exe --vanilla): >>> >>>> is.na(strptime("5/3/1992", format="%m/%d/%Y")) >>> [1] TRUE >>> >>>> is.na(strptime("5/2/1992", format="%m/%d/%Y")) >>> [1] FALSE >>> >>>> sessionInfo() >>> R version 2.12.1 (2010-12-16) >>> Platform: i386-pc-mingw32/i386 (32-bit) >>> >>> locale: >>> [1] LC_COLLATE=English_United States.1252 >>> [2] LC_CTYPE=English_United States.1252 >>> [3] LC_MONETARY=English_United States.1252 >>> [4] LC_NUMERIC=C >>> [5] LC_TIME=English_United States.1252 >>> >>> attached base packages: >>> [1] stats graphics grDevices utils datasets methods base >>> >>> ______________________________________________ >>> R-help@r-project.org mailing list >>> https://stat.ethz.ch/mailman/listinfo/r-help >>> PLEASE do read the posting guide >>> http://www.R-project.org/posting-guide.html >>> and provide commented, minimal, self-contained, reproducible code. >>> >> >> >> > > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.