How can I use onehot encoding and dummyVars in a vector?

Question

Im new to R and Stackoverflow.

I'm currently trying to apply onehot encoding to a vector. I tried to use dummyvars to accomplish it.

v <- sample(c("cat", "dog", "mouse"), 1000, replace = TRUE);

dmy <- dummyVars(" ~ .", data = v) <br />
dat_transformed <- data.frame(predict(dmy, newdata = v))
dat_transformed

I can make it work in data frames or data tables but not in a vector. How can I work around it?

Thanks.

Answer 1

The default method of dummyVars expects data to be a data.frame so you would need to wrap the vector in a data.frame

library(caret)
#> Loading required package: lattice
#> Loading required package: ggplot2

v <- data.frame(x = sample(c("cat", "dog", "mouse"), 10, replace = TRUE))

dmy <- dummyVars(~x, data = v)
dat_transformed <- predict(dmy, newdata = v)
dat_transformed
#>    x.cat x.dog x.mouse
#> 1      1     0       0
#> 2      0     0       1
#> 3      0     0       1
#> 4      0     1       0
#> 5      1     0       0
#> 6      0     1       0
#> 7      1     0       0
#> 8      0     0       1
#> 9      1     0       0
#> 10     1     0       0