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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