Simply pass your data frame into the following function:
data_types <- function(frame) {
res <- lapply(frame, class)
res_frame <- data.frame(unlist(res))
barplot(table(res_frame), main="Data Types", col="steelblue", ylab="Number of Features")
}
to produce a plot of all data types in your data frame. For the iris dataset we get the following:
data_types(iris)