[R] duplicate rows with new time series

[Gabor Grothendieck]

On Thu, May 9, 2013 at 7:24 PM, Ye Lin <yelin at lbl.gov> wrote:
> Hey All,
>
> I want to duplicate the records but add a new "timestamp" columns as new
> time series, but I dont know how to do that.
>
> my dataset(dat1) looks like this:
>
> No.          TimeStamp          Var1
>
> 1         2012-06-18 06:00:00    3
> 2         2012-06-18 06:06:00     4
>
> I use this code to do duplication:
>
> dat1[rep(1:nrow(dat1),each=3),]
>
> But I dont know how to change the timeStamp. I would like the final output
> be sth like this:
>
> No.          TimeStamp          Var1
>
> 1         2012-06-18 06:00:00    3
> 2         2012-06-18 06:02:00    3
> 3         2012-06-18 06:04:00     3
> 4         2012-06-18 06:06:00     4
> 5         2012-06-18 06:08:00     4
> 6         2012-06-18 06:10:00     4
>
> So basically the old time interval is 6 min, but the new ones I would like
> to have is 2 min.

Assuming dat2 is the result of the line of R code above that does the
replication and that TimeStamp is of POSIXct class try this:

    dat2$TimeStamp <- dat2$TimeStamp + seq(0, 4, 2))

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