I really don't understand what you want to achieve and how your data presents
itself.
You have several combinations of trial/subject which are unique?
There is a variable for each such combination that you want to test against
(tt)?
In addition you have data on each such combination (several sets with 17
columns ) ?
or each column is a subject and each row a trial or something along those lines?
On 01.11.2012, at 16:18, mardijk wrote:
> Hello,
>
> As I am new with R I am completely stuck in resolving a, no doubt, easy
> problem.
>
> I have a dataset with an enormous amount of rows and 17 columns. I need to
> know per trial and subject number if another variable (tt) exceeds a
> maximum. If this is true than the last 5000 rows of that specific trial for
> that subject number needs to be deleted.
>
> But I am completely stuck on how to do so. After various attempts I have
> finally come up with the following (which obviously does not work).
>
>
> if (dat["tt"]>6000
> ){
> return(
> tail(dattest[,c("Trial", "Subj" )],n=5000) <- NA
> }
>
> Can anybody explain what I need to do?
>
> Thank you so much!
>
>
>
>
>
>
> --
> View this message in context:
> http://r.789695.n4.nabble.com/Select-the-last-rows-of-when-specific-conditions-are-met-tp4648133.html
> Sent from the R help mailing list archive at Nabble.com.
>
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