is.unsorted Test if an Object is Not Sorted

Description

Test if an object is not sorted (in increasing order), without the cost of sorting it.

Usage

is.unsorted(x, na.rm = FALSE, strictly = FALSE)

Arguments

x	an R object with a class or a numeric, complex, character, logical or raw vector.
na.rm	logical. Should missing values be removed before checking?
strictly	logical indicating if the check should be for strictly increasing values.

Details

is.unsorted is generic: you can write methods to handle specific classes of objects, see InternalMethods.

Value

A length-one logical value. All objects of length 0 or 1 are sorted. Otherwise, the result will be NA except for atomic vectors and objects with an S3 class (where the >= or > method is used to compare x[i] with x[i-1] for i in 2:length(x)) or with an S4 class where you have to provide a method for is.unsorted().

Note

This function is designed for objects with one-dimensional indices, as described above. Data frames, matrices and other arrays may give surprising results.

See Also

sort, order.