[R] Date Time in R

[Duncan Murdoch]

On 26/07/2016 7:05 AM, Shivi Bhatia wrote:
> Hi Team,
>
> This scenario may have come across a number of times however i checked
> nabble & SO and couldn't find a solution hence request assistance.
>
> I have a date variable in my data-set eir. The class of this var was
> character while i had read the file in r studio. Example of date - 05-30-16
>
> To change this i have used eir$date<- as.Date(eir$date, "%m-%d-%y"). This
> converts it to a date variable. However when i check few obs
> with head(eir$date) all the results are <NA>.

I think you don't have character data like that, because I see

 > as.Date("05-30-16", "%m-%d-%y")
[1] "2016-05-30"

I'd guess eir$date is really a factor, because character data is 
frequently changed to factor automatically.  If that's the case, this 
should work for the conversion:

as.Date(as.character(eir$date), "%m-%d-%y")

If that doesn't work, you'll need to post something reproducible.

Duncan Murdoch

> I also need to create weekdays from this date variable but until i get this
> resolved i cant find a weekday. For weekday i have used:
> eir$week<- (eir$date)
> eir$week<- weekdays(as.Date(eir$week))
> class(eir$week)
> eir$week<- as.factor(eir$week)
> head(eir$week)
>
> Head of this eir$week results again as expected in <NA> but shows Levels:
> Friday Monday Saturday Sunday Thursday Tuesday Wednesday
>
> Not sure what i should do here. Kindly suggest.
>
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