[R] Want to exclude a column when using sample function

Jeff Newmiller jdnewmil at dcn.davis.ca.us
Wed Jul 14 19:41:44 CEST 2010


I would use "melt" from the reshape package so that "sample" could be used, rather than trying to process various selections of columns from a wide data.frame.

"Addi Wei" <addiwei at gmail.com> wrote:

>
>Sorry to post multiple questions, but this is still related to the sample
>function.
>
>In my previous example, how do I save/store the current sample so when I run
>sample again (after analysis) I can exclude the samples that were previously
>chosen. 
>
>For example if I have 180 factors or columns...and I sample 10 from the data
>set using:
>sample10 <- sample(data, 10, replace=FALSE) 
>
>##and then from this sample of 10, I'll run my analysis, and then I wish to
>randomly replace 3 samples out of 10, with 3 new factors from the list of
>180 factors (that have not been chosen thus far).  I wish to store all the
>factors that have been chosen for analysis into an object to avoid me going
>back and picking those same factors again....  
>-- 
>View this message in context: http://r.789695.n4.nabble.com/Want-to-exclude-a-column-when-using-sample-function-tp2287988p2289118.html
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>
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