Convert integer to class Date

Question

I have an integer which I want to convert to class Date. I assume I first need to convert it to a string, but how?

My attempt:

v <- 20081101
date <- as.Date(v, format("%Y%m%d"))

Error in charToDate(x) : character string is not in a standard unambiguous format

Using paste() works, but is that really the correct way to do the conversion?

date <- as.Date(paste(v), format("%Y%m%d"))
date
[1] "2008-11-01"

class(date)
# [1] "Date"

Gavin Simpson · Accepted Answer · 2015-11-18T18:02:54.580

59

as.character() would be the general way rather than use paste() for its side effect

> v <- 20081101
> date <- as.Date(as.character(v), format = "%Y%m%d")
> date
[1] "2008-11-01"

(I presume this is a simple example and something like this:

v <- "20081101"

isn't possible?)

edited Nov 18 '15 at 18:02

answered Nov 05 '10 at 08:27

Gavin Simpson

1

@DavidArenburg I think I have a typo as I've never, not once, used `as.Date` the way I show above. – Gavin Simpson Nov 18 '15 at 18:02

score 19 · Answer 2 · answered Jun 08 '12 at 02:14

19

Another way to get the same result:

date <- strptime(v,format="%Y%m%d")

answered Jun 08 '12 at 02:14

Vivi

3

interesting. I didn't realize that `strptime` would automatically coerce/handle numeric values ... – Ben Bolker Jun 08 '12 at 07:04

score 3 · Answer 3 · answered Jul 12 '20 at 10:01

3

You can use ymd from lubridate

lubridate::ymd(v)
#[1] "2008-11-01"

Or anytime::anydate

anytime::anydate(v)
#[1] "2008-11-01"

answered Jul 12 '20 at 10:01

Ronak Shah

3 Answers3