How to check if each element in a vector is integer or not in R?

Question

Say, I have a vector y, and I want to check if each element in y is integer or not, and if not, stop with an error message. I tried is.integer(y), but it does not work.

Answer 1

I went in a completely different direction then Tim (I like his better though my approach works on a mixed vector that's a character vector with integers etc.):

int.check <- function(vect) {
    vect <- as.character(vect)
    sapply(vect, function(x) all(unlist(strsplit(x, ""))%in% 0:9))
}

x <- c(2.0, 1111,"x", 2.4)
int.check(x)

EDIT: altered the function as it only worked on character vectors.

This works on vectors of the class character as well in case you have a character vector with various number intermixed but that have been coerced to character.