[R] Creating a Date Field

[Jim Lemon]

Hi Phillip,
Try this:

as.Date(c("20180329","20180330","20180331"),"%Y%m%d")
[1] "2018-03-29" "2018-03-30" "2018-03-31"

Note that the format argument has to match the date format exactly.

Jim

On Wed, Sep 25, 2019 at 9:54 AM Phillip Heinrich <herd_dog using cox.net> wrote:
>
> The date is imbedded in the GameID character field so I created a date vector with the following code:
>
> ari18.test3$date <- substring(ari18.test3$GameID,4,11)  And then created a new dataframe with just the Game ID and date vectors.  The date field is a character as shown by the str() command. str(test)
> 'data.frame':   3 obs. of  2 variables:
>  $ GameID: Factor w/ 3 levels "ARI201803290",..: 1 2 3
>  $ date  : chr  "20180329" "20180330" "20180331"           GameID     date
> 1   ARI201803290 20180329
> 81  ARI201803300 20180330
> 165 ARI201803310 20180331
> > My notes from about a week ago say that the following code will turn “date” into a date field: test$date <- as.Date(test$date,format="%Y %M %D")  date becomes a date field but the data disappears into NA   str(test)
> 'data.frame':   3 obs. of  2 variables:
>  $ GameID: Factor w/ 3 levels "ARI201803290",..: 1 2 3
>  $ date  : Date, format: NA NA NA  What am I missing here?
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>
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