On 6/22/2011 1:03 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: > >> strptime("5/2/1992", format="%m/%d/%Y") > [1] "1992-05-02" >> is.na(strptime("5/2/1992", format="%m/%d/%Y")) > [1] FALSE >> strptime("5/3/1992", format="%m/%d/%Y") > [1] "1992-05-03" >> is.na(strptime("5/3/1992", format="%m/%d/%Y")) > [1] FALSE > > My suspicion is that you imported the data from a spreadsheet and > there's some formatting glitch that's not showing up. If you type the > string "5/3/1992" into the command by hand, do you still get the same > result?
Copy and pasting the above lines reproduces the problem on my setup. > If so, then we need to know your OS and version of R, at least. > sessionInfo() R version 2.12.1 (2010-12-16) Platform: i386-pc-mingw32/i386 (32-bit) locale: [1] LC_COLLATE=English_United States.1252 LC_CTYPE=English_United States.1252 LC_MONETARY=English_United States.1252 LC_NUMERIC=C [5] LC_TIME=English_United States.1252 attached base packages: [1] grid grDevices datasets splines graphics stats tcltk utils methods base other attached packages: [1] ggplot2_0.8.9 proto_0.3-8 reshape_0.8.4 plyr_1.4 svSocket_0.9-51 TinnR_1.0.3 R2HTML_2.2 Hmisc_3.8-3 survival_2.36-2 loaded via a namespace (and not attached): [1] cluster_1.13.2 digest_0.4.2 lattice_0.19-17 svMisc_0.9-61 tools_2.12.1 > >> Any idea what's going on with this? Running strptime against all dates >> from around 1946, only 5/3/1992 was converted as "NA". Even stranger, >> it still seems to have a value associated with it (even though is.na >> thinks it's NA): >> >>> strptime("5/3/1992", format="%m/%d/%Y") >> [1] "1992-05-03" > > This makes no sense to me. > > Sarah > > ______________________________________________ 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.