How do I get the classes of all columns in a data frame?
r
Solution
One option is to use `lapply` and `class`. For example:
> foo <- data.frame(c("a", "b"), c(1, 2))
> names(foo) <- c("SomeFactor", "SomeNumeric")
> lapply(foo, class)
$SomeFactor
[1] "factor"
$SomeNumeric
[1] "numeric"
Another option is `str`:
> str(foo)
'data.frame': 2 obs. of 2 variables:
$ SomeFactor : Factor w/ 2 levels "a","b": 1 2
$ SomeNumeric: num 1 2
Problem
What is an easy way to find out what class each column is in a data frame?