# First let's build a very large data.table with random numbers
require(data.table)
M <- as.data.table(matrix(runif (3e4), ncol = 10))
M_rounded <- fast_round(M, 2)
# Lets add some character
M[, stringColumn := "a string"]
# And use our function
M_rounded <- fast_round(M, 2)
# It still work :) and you don't have to worry about the string.
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