Select subset of columns in data.table R [duplicate]

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Use with=FALSE:

cols = paste("V", c(1,2,3,5), sep="")

dt[, !cols, with=FALSE]

I suggest going through the “Introduction to data.table” vignette.

Update: From v1.10.2 onwards, you can also do:

dt[, ..cols]

See the first NEWS item under v1.10.2 here for additional explanation.

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