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I have a date in format "%e-%a-%y" example: "13-Mar-15"

I need to convert this date in format "%Y-%m-%d"

I have tried format(example, "%Y-%m-%d") without success. Also tried

format(as.POSIXct(example, format="%e-%a-%y"), format="%Y-%m-%d")

without success.

Edit: I know what happened I had the wrong format:"%e-%a-%y".
It needed to be "%d-%b-%y" It was late and when I wrote my initial format, so I wasn't thinking very clearly: "%a" was for the abbreviated day.
The error was that I was trying to convert without the proper source format. "%b" is the abbreviated month, which should work for this question.

TTR
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  • Posting answers, is not the only way to help. Editing a badly formatted question is important too. Especially for future readers. – David Arenburg Nov 16 '15 at 09:31

2 Answers2

2

You had the wrong format :

as.Date("13-Mar-15", "%d-%b-%y")
[1] "2015-03-13"

For the formats, %d is the day, %b is the abbreviated month and %y the year (two-digits)

%a is an abbreviated weekday name. You could also use 

as.Date("13-Mar-15", "%e-%b-%y")
[1] "2015-03-13"

as %e is also the day (format 1-31) where %d is 01-31. read ?strptime for more info on the date format.

etienne
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1

Another option is lubridate, where it is easy to convert to POSIXct class.

library(lubridate)
dmy(v1)
#[1] "2015-03-13 UTC"

data

v1 <-  "13-Mar-15"
akrun
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