Change categoric variable to a dumy matrix in r

Question

I like to use randomforest in R, but i get a category with more than 100 levels, so, i can't use randomforest directly. I like to change the variable with the categories into a matrix with binary values (con column for category an values true/false). Is there any function to do this directly?

Original column
1
2
3
4
4

Target columns
1  2  3  4  
1  0  0  0
0  1  0  0
0  0  1  0
0  0  0  1
0  0  0  1

Kind regards.

@李哲源 OK, I have now tested it with a factor and your suggestion does work. I should have read the question more carefully. — Rui Barradas, Jul 24 '18 at 17:14

score 1 · Answer 1 · edited Jun 20 '20 at 09:12

1

An option would be table

table(seq_along(v1), v1)

It does work even if it is an integer/numeric column

data

v1 <- <- c(1, 2, 3, 4, 4)

edited Jun 20 '20 at 09:12

Community

1
1

answered Jul 24 '18 at 16:23

akrun

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Finaly I has been solved with the library caret like this: library(caret) dmy ) )) – Javier Aug 01 '18 at 06:43

Change categoric variable to a dumy matrix in r

1 Answers1

data