[datatable-help] subsetting .SD

[Matthew Finkbeiner]

I know that we shouldn't subset .SD, but I would like to return the row
from each group that corresponds to a max value in one of the columns.
 Here's how I'm doing it currently:

maxrows<- df.dt[, .SD[which(X1== max(X1)),], by = list(Var1, Var2, Var3)]

Is there a better way?

Thank you kindly,

Matthew
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