[R] Changing Date Variables as Continuous Variables

[jim holtman]

Here is how to convert your column of factors into Dates:

> x <- read.table(text = '2/10/2011
+ 2/20/2011
+ 3/4/2011')
> # read in as factors
> str(x)
'data.frame':   3 obs. of  1 variable:
 $ V1: Factor w/ 3 levels "2/10/2011","2/20/2011",..: 1 2 3
> # convert to Date
> x$date <- as.Date(as.character(x$V1), format = "%m/%d/%Y")
> x
         V1       date
1 2/10/2011 2011-02-10
2 2/20/2011 2011-02-20
3  3/4/2011 2011-03-04
> str(x)
'data.frame':   3 obs. of  2 variables:
 $ V1  : Factor w/ 3 levels "2/10/2011","2/20/2011",..: 1 2 3
 $ date: Date, format: "2011-02-10" "2011-02-20" "2011-03-04"


On Sat, Nov 3, 2012 at 8:09 PM, hoguejm <hoguejm at gmail.com> wrote:
> I am very new to R, so I apologize if this question is trivial.
>
> I have a row in my data of dates in the format mm/dd/yyyy; about 3500 rows.
>
> I am using this variable in a logistic regression model, and need to treat
> it as continuous, not a factor as r has decided it is.
>
> I tried the as.numeric function but it resulted in all NA's and the message:
> "NAs introduced by coercion "
>
> If anyone knows a solution, I would greatly appreciate it.
>
> Cheers,
> Jake
>
>
>
> --
> View this message in context: http://r.789695.n4.nabble.com/Changing-Date-Variables-as-Continuous-Variables-tp4648354.html
> Sent from the R help mailing list archive at Nabble.com.
>
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-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?
Tell me what you want to do, not how you want to do it.