Create new dummy variable columns from categorical variable

Question

I have a several data sets with 75,000 observations and a type variable that can take on a value 0-4. I want to add five new dummy variables to each data set f

Answer 1

What about using model.matrix()?

> binom <- data.frame(data=runif(1e5),type=sample(0:4,1e5,TRUE))
> head(binom)
       data type
1 0.1412164    2
2 0.8764588    2
3 0.5559061    4
4 0.3890109    3
5 0.8725753    3
6 0.8358100    1
> inds <- model.matrix(~ factor(binom$type) - 1)
> head(inds)
  factor(binom$type)0 factor(binom$type)1 factor(binom$type)2 factor(binom$type)3 factor(binom$type)4
1                   0                   0                   1                   0                   0
2                   0                   0                   1                   0                   0
3                   0                   0                   0                   0                   1
4                   0                   0                   0                   1                   0
5                   0                   0                   0                   1                   0
6                   0                   1                   0                   0                   0