R: Expanding an R factor into dummy columns for every factor level

Question

I have a quite big data frame in R with two columns. I am trying to make out of the Code column (factor type with 858 levels) the dummy variables.

Answer 1

This worked for me perfectly:

library(reshape2)
m <- acast(data = d, User ~ Code)

The only thing was that it produced NAs, instead of 0s, but this can be easily changed with this:

m[is.na(m)] <- 0