Dates and times are notoriously tricky to get right and the fact that the printed representation is so different from the internal (which is basically just a count of seconds) doesn't really help: to make this fully reproducible, could you supply us with the output of
dput(head(read.table("data1.txt",header=T,sep="\t"), 30)) dput(head(read.table("data2.txt",header=T,sep="\t"), 30)) as well? Thanks! Michael On Sun, May 27, 2012 at 3:56 PM, Des Callaghan <des.callag...@ecostudy.co.uk> wrote: > Hello Forum, > > > > I have a problem with the strptime function. With the 'data1' dataset below > it works fine, but with the 'data2' dataset something goes wrong (see final > line below). Both data1 and data2 are in exactly the same original format, > the only difference is that they span different dates. Please help, since it > is driving me nuts! Many thanks. > > > > Best wishes, > > Des > > - > >> data1=read.table("data1.txt",header=T,sep="\t") > >> datetime1=strptime(data1$Date, "%a %b %d %H:%M:%S %Y") #example line from > data1 'Tue Aug 16 03:00:01 2011' > >> summary(datetime1) > > Min. 1st Qu. > Median Mean > > "2011-08-15 21:00:01 BST" "2011-10-08 01:00:01 BST" "2011-11-30 05:00:01 > GMT" "2011-11-30 04:38:47 GMT" > > 3rd Qu. Max. > > "2012-01-22 09:00:01 GMT" "2012-03-15 13:00:01 GMT" > >> min(datetime1) > > [1] "2011-08-15 21:00:01 BST" > >> data2=read.table("data2.txt",header=T,sep="\t") > >> datetime2=strptime(data2$Date, "%a %b %d %H:%M:%S %Y") #example line from > data2 'Sun Nov 27 13:07:01 2011' > >> summary(datetime2) > > Min. 1st Qu. > Median Mean > > "2011-11-27 01:07:01 GMT" "2012-01-09 20:07:01 GMT" "2012-02-22 15:07:01 > GMT" "2012-02-22 15:26:16 GMT" > > 3rd Qu. Max. > > "2012-04-06 12:07:01 BST" "2012-05-20 07:07:01 BST" > >> min(datetime2) > > [1] NA > > > > > > > > > > > [[alternative HTML version deleted]] > > ______________________________________________ > 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.