Are even
are_even(x, check_integerish = TRUE)which_are_even(x, check_integerish = TRUE)
An integer vector. Double vectors may also be used.
(logical, default: TRUE) Should the
values in x be checked for non-integer values
if x is a double vector. If TRUE
and values are found to be non-integer a warning is emitted.
For are_even, a logical vector the same length as x,
TRUE whenever x is even.
For which_are_even the integer positions of even values in x.