Convert a factor column to multiple boolean columns

Question

Given data that looks like:

library(data.table)
DT <- data.table(x=rep(1:5, 2))

I would like to split this data into 5 boolean columns t

Answer 1

There is also nnet::class.ind

library(nnet)

cbind(DT, setnames(as.data.table(DT[, class.ind(x)]),paste0('col', unique(DT$x))))