Generate Dummy Variables From Data Frame

Question

I have a data.frame with the following properties:

list1 <- c(145540,145560, 157247, 145566)
list2 <- c(166927, NA, NA, NA)
list3 <- c(145592, 145560, 145566, NA)
df <- data.frame(list1, list2, list3)

I would like to generate a dummy variables for each of the included ids. The result should look like this.

list, 145540, 145560, 145566,145592,157247,166927 (= all possible ids in the data)

list1, 1, 1, 1, 0, 1, 0

list2, 0, 0, 0, 0, 0, 1

list3, 0, 1, 1, 1, 0, 0

Any ideas how to achieve this? Thank You!

Answer 1

My answer is a little clunkier, but here it is:

all.vals <- na.omit(unique(unlist(df)))  ## get full set of values

Use a for loop for greater clarity:

df2 <- list()
for (i in seq_along(df))
  df2[[i]] <-
  sapply(all.vals,
         function(x) as.numeric(x %in% df[[i]]))
names(df2) <- names(df)
## add labels as the first column:
df2 <- data.frame(all.vals,df2)

Result:

  all.vals list1 list2 list3
1   145540     1     0     0
2   145560     1     0     1
3   157247     1     0     0
4   145566     1     0     1
5   166927     0     1     0
6   145592     0     0     1