Generate a dummy-variable

Question

I have trouble generating the following dummy-variables in R:

I\'m analyzing yearly time series data (time period 1948-2009). I have two questions:

1. <

Answer 1

Another way is to use mtabulate from qdapTools package, i.e.

df <- data.frame(var = sample(c("A", "B", "C"), 5, replace = TRUE))
  var
#1   C
#2   A
#3   C
#4   B
#5   B

library(qdapTools)
mtabulate(df$var)

which gives,

  A B C
1 0 0 1
2 1 0 0
3 0 0 1
4 0 1 0
5 0 1 0