is_positive_integer: A Convenient Version of is.integer
In chinese.misc: Miscellaneous Tools for Chinese Text Mining and More

Description Usage Arguments Details Value Examples

This function checks if all elements of an object can be taken to be valid integers.

1	is_positive_integer(x, len = NULL)

`x`	an object to be checked
`len`	numeric vector specifying the allowed length of the `x`. If the length of the checked object is not in `len`, the function will return `FALSE`, even when it is a positive integer vector. The default is `NULL`, which means any length is OK.

The reasons to use is_positive_integer are:

(1) We often check if an object is a vector of positive integer. But is.numeric cannot do this because it also returns TRUE for a numeric matrix.
(2) Sometimes is.integer returns a too strict result. For example, is.integer(3.0) returns FALSE, but the number 3.0 is valid in codes such as rep(10, 3.0), that is to say, as long as a number can be taken to be a valid integer, we take it to be a integer, even when is.integer returns FALSE.
(3) is_positive_integer returns FALSE for length = 0 object, even when it is integer(0). To let the function return this result is because integer of length 0 is a invalid input for many functions.
(4) is_positive_integer returns FALSE for any object that contains NA, so that object that gets a TRUE from this function is more likely to be a valid value to be passed to other functions.

TRUE or FALSE

is_positive_integer(NULL)
is_positive_integer(as.integer(NA))
is_positive_integer(integer(0))
is_positive_integer(3.0)
is_positive_integer(3.3)
is_positive_integer(1:5)
is_positive_integer(1:5, len = c(2, 10))
is_positive_integer(1:5, len = c(2:10))