Test if an Object is Not Sorted
Test if an object is not sorted (in increasing order), without the cost of sorting it.
is.unsorted(x, na.rm = FALSE, strictly = FALSE)
- an R object with a class or a numeric, complex, character, logical or raw vector.
- logical. Should missing values be removed before checking?
- logical indicating if the check should be for strictly increasing values.
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().
%% FIXME: rather want '>' and '>=' methods for S4 classes be sufficient
This function is designed for objects with one-dimensional indices, as described above. Data frames, matrices and other arrays may give surprising results. Support for raw vectors was added in R 3.1.0.