| vec_match {vctrs} | R Documentation |
vec_in() returns a logical vector based on whether needle is found in
haystack. vec_match() returns an integer vector giving location of
needle in haystack, or NA if it's not found.
vec_match( needles, haystack, ..., na_equal = TRUE, needles_arg = "", haystack_arg = "" ) vec_in( needles, haystack, ..., na_equal = TRUE, needles_arg = "", haystack_arg = "" )
needles, haystack |
Vector of
|
... |
These dots are for future extensions and must be empty. |
na_equal |
If |
needles_arg, haystack_arg |
Argument tags for |
vec_in() is equivalent to %in%; vec_match() is equivalent to match().
A vector the same length as needles. vec_in() returns a
logical vector; vec_match() returns an integer vector.
In most cases places in R, missing values are not considered to be equal,
i.e. NA == NA is not TRUE. The exception is in matching functions
like match() and merge(), where an NA will match another NA.
By vec_match() and vec_in() will match NAs; but you can control
this behaviour with the na_equal argument.
vec_cast_common() with fallback
hadley <- strsplit("hadley", "")[[1]]
vec_match(hadley, letters)
vowels <- c("a", "e", "i", "o", "u")
vec_match(hadley, vowels)
vec_in(hadley, vowels)
# Only the first index of duplicates is returned
vec_match(c("a", "b"), c("a", "b", "a", "b"))