I tried it, but it doesn't work. The time column is blank then. DF$time = substring(DF$time, first=as.Date('1999-01-01), last=as.Date('2005-12-30'))
On Sat, Dec 31, 2016 at 10:52 AM, David Winsemius <dwinsem...@comcast.net> wrote: > > > On Dec 31, 2016, at 9:26 AM, lily li <chocol...@gmail.com> wrote: > > > > Hi all, > > > > Thanks for your help. Now I can convert data to the format "yyyy-mm-dd > > hh:mm:ss", but how to convert it to "yyyy-mm-dd"? The datasets are txt > > files, not from excel. > > Use: as.Date > > > > On Fri, Dec 30, 2016 at 3:01 PM, Duncan Mackay <dulca...@bigpond.com> > wrote: > > > >> Hi > >> > >> Is this the output from Excel? > >> If so format it in Excel for a date format not a date-time format . > >> Depending how the dates were inputted into Excel and the Excel setup a > date > >> may not be a date format. > >> There are no rules with microsoft formatting so beware! > >> > >> > >> Regards > >> > >> Duncan > >> > >> Duncan Mackay > >> Department of Agronomy and Soil Science > >> University of New England > >> Armidale NSW 2351 > >> Email: home: mac...@northnet.com.au > >> > >> -----Original Message----- > >> From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of lily li > >> Sent: Saturday, 31 December 2016 05:38 > >> To: Rui Barradas > >> Cc: R mailing list > >> Subject: Re: [R] about data format in R > >> > >> Hi Rui, > >> > >> Thanks for your reply. When I read in data using my code, the first > column > >> ranges from 0 to 1. So when I use the code you wrote, it shows the error > >> message: > >> Error in as.POSIXct.numeric(DF$Date, format = "%m/%d/%Y-%H:%M:%S") : > >> 'origin' must be supplied > >> > >> > >> On Fri, Dec 30, 2016 at 11:23 AM, Rui Barradas <ruipbarra...@sapo.pt> > >> wrote: > >> > >>> Hello, > >>> > >>> Have you tried > >>> > >>> df$date <- as.POSIXct(dat$date, format = "%m/%d/%Y-%H:%M:%S") > >>> > >>> ? > >>> > >>> Hope this helps, > >>> > >>> Rui Barradas > >>> > >>> > >>> > >>> Em 30-12-2016 17:40, lily li escreveu: > >>> > >>>> Hi R users, > >>>> > >>>> I'm trying to read in data, and then plot time series data. However, I > >>>> have > >>>> some problems. In my dataset, the first column represents time, and in > >> the > >>>> format: > >>>> mm/dd/yyyy-hr:min:sec; For example, 10/01/1995-00:00:00, > >>>> 10/01/1995-06:00:00, etc. > >>>> > >>>> df: > >>>> date evap precip intercept > >>>> 10/01/1995-00:00:00 1.5 2 0.2 > >>>> 10/01/1995-12:00:00 1.7 2.2 0.1 > >>>> 10/02/1995-00:00:00 1.5 1.8 0.3 > >>>> ... > >>>> > >>>> My code is like this > >>>> file1 = read.table('df', head=T) > >>>> > >>>> When I read in data, I found that it read incorrectly. How to format > >> when > >>>> read in data? Thanks. > >>>> > >>>> [[alternative HTML version deleted]] > >>>> > >>>> ______________________________________________ > >>>> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > >>>> https://stat.ethz.ch/mailman/listinfo/r-help > >>>> PLEASE do read the posting guide http://www.R-project.org/posti > >>>> ng-guide.html > >>>> and provide commented, minimal, self-contained, reproducible code. > >>>> > >>>> > >> > >> [[alternative HTML version deleted]] > >> > >> ______________________________________________ > >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > >> 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 -- To UNSUBSCRIBE and more, see > >> 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. > >> > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > > 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. > > David Winsemius > Alameda, CA, USA > > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.