[R] date

[Martin Maechler]

>>>>> John Kane 
>>>>>     on Tue, 17 Dec 2019 20:28:17 -0500 writes:

    > library(lubridate)
    > gs$dat1  <-  mdy(gs$date)

there's really no reason for going beyond base R.

Using the proper format as per Patrick and Peter's advice
(below) is perfectly clear and actually
more robust (for the next data set etc)
than going via "good guessing" in extra packages.

    > On Tue, 17 Dec 2019 at 18:38, peter dalgaard <pdalgd using gmail.com> wrote:
    >> 
    >> ...and switch the order, and use %y for 2-digit years.
    >> 
    >> > On 17 Dec 2019, at 23:57 , Patrick (Malone Quantitative) <malone using malonequantitative.com> wrote:
    >> >
    >> > Try putting / instead of - in your format, to match the data.
    >> >
    >> > On Tue, Dec 17, 2019 at 5:52 PM Val <valkremk using gmail.com> wrote:
    >> >>
    >> >> Hi All,
    >> >>
    >> >> I wanted to to convert character date  mm/dd/yy  to YYYY-mm-dd
    >> >> The sample data and my attempt is shown below
    >> >>
    >> >> gs <-read.table(text="ID date
    >> >> A1   09/27/03
    >> >> A2   05/27/16
    >> >> A3   01/25/13
    >> >> A4   09/27/19",header=TRUE,stringsAsFactors=F)
    >> >>
    >> >> Desired output
    >> >>  ID     date      d1
    >> >> A1 09/27/03 2003-09-27
    >> >> A2 05/27/16 2016-05-27
    >> >> A3 01/25/13 2012-04-25
    >> >> A4 09/27/19 2019-09-27
    >> >>
    >> >> I used this
    >> >> gs$d1 = as.Date(as.character(gs$date), format = "%Y-%m-%d")
    >> >>
    >> >> but I got NA's.
    >> >>
    >> >> How do I get my desired result?
    >> >> 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.
    >> >
    >> > ______________________________________________
    >> > 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.
    >> 
    >> --
    >> Peter Dalgaard, Professor,
    >> Center for Statistics, Copenhagen Business School
    >> Solbjerg Plads 3, 2000 Frederiksberg, Denmark
    >> Phone: (+45)38153501
    >> Office: A 4.23
    >> Email: pd.mes using cbs.dk  Priv: PDalgd using gmail.com
    >> 
    >> ______________________________________________
    >> 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.



    > -- 
    > John Kane
    > Kingston ON Canada

    > ______________________________________________
    > 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.