Hi Val, Try this: dat=read.csv("myfile.csv",stringsAsFactors=FALSE)
However, the apparently silent conversion of format is a mystery to me. The only time I have struck something like this was when exporting dates from Excel some years ago, and there was a silent conversion to mm/dd/yyyy format if the dates were in dd/mm/yyyy format. Could you post some sample data? Jim On Fri, Nov 5, 2021 at 8:44 AM Val <valkr...@gmail.com> wrote: > > IHi All, l, > > I am reading a csv file and one of the columns is named as "mydate" > with this form, 2019-09-16. > > I am reading this file as > > dat=read.csv("myfile.csv") > the structure of the data looks like as follow > > str(dat) > mydate : chr "09/16/2019" "02/21/2021" "02/22/2021" "10/11/2017" ... > > Please note the format has changed from YYYY-mm-dd to mm/dd/YYYY > When I tried to change this as a Date using > > as.Date(as.Date(mydate, format="%m/%d/%Y" ) > I am getting this error message > Error in charToDate(x) : > characte string is not in a standard unambiguous format > > My question is, > 1. how can I read the file as it is (i.e., without changing the date format) ? > 2. why does R change the date format? > > Thank you, > > ______________________________________________ > 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.