[R] Date

[Val]

Thank you All.
The issue was not reading different file. I just mistyped the column
name, instead of typing My_date I typed mydate in the email.  The
problem is solved by using this
    dat=read.csv("myfile.csv",stringsAsFactors=FALS)
suggested by Jim.

On Thu, Nov 4, 2021 at 7:58 PM Jeff Newmiller <jdnewmil using dcn.davis.ca.us> wrote:
>
> Then you are looking at a different file... check your filenames. You have imported the column as character, and R has not yet recognized that it is supposed to be a date, so it can only show what it found.
>
> You will almost certainly find your error if you make a reproducible example.
>
> On November 4, 2021 5:30:22 PM PDT, Val <valkremk using gmail.com> wrote:
> >Jeff,
> >
> >The date from y data file looks like as follow in the Linux environment,
> >My_date
> >2019-09-16
> >2021-02-21
> >2021-02-22
> >2017-10-11
> >2017-10-10
> >2018-11-11
> >2017-10-27
> >2017-10-30
> >2019-05-20
> >
> >On Thu, Nov 4, 2021 at 5:00 PM Jeff Newmiller <jdnewmil using dcn.davis.ca.us> wrote:
> >>
> >> You are claiming behavior that is not something R does, but is something Excel does constantly.
> >>
> >> Compare what your data file looks like using a text editor with what R has imported. Absolutely do not use a spreadsheet program to do this.
> >>
> >> On November 4, 2021 2:43:25 PM PDT, Val <valkremk using 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 using 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.
> >>
> >> --
> >> Sent from my phone. Please excuse my brevity.
>
> --
> Sent from my phone. Please excuse my brevity.