Date

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 at 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 at 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 at 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,

--
Sent from my phone. Please excuse my brevity.

--
Sent from my phone. Please excuse my brevity.