Message-ID: <39B6DDB9048D0F4DAD42CB26AAFF0AFA076CE3@usctmx1106.merck.com>
Date: 2005-03-25T13:24:14Z
From: Liaw, Andy
Subject: newbie's question about dataframe
Something like this should do it:
dat$Z <- with(dat, as.numeric(Y >= Y[order(Y, decreasing=TRUE)[10]]))
Andy
> From: Wensui Liu
>
> I have a dataframe containing X and Y. Right now, I want to create
> another variable in the dataframe, named Z, such that for Z = 1 for
> the top 10 largest value of Y and Z = 0 for the rest values of Y.
>
> I really appreciate your help. Have a great weekend.
>
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