Control treatment of NAs. If TRUE, missing values in the data are put last; if FALSE, they are put first; if NA, they are removed; if "keep" they are kept with rank NA.
internal
Internal use only. Temporary variable. Will be removed.
verbose
Print tracing information.
...
Not sure yet. Should be consistent with base R.
Value
The input in sorted order.
Details
Process will raise error if x contains negative values.
Unless x is already sorted fsort will redirect processing to slower single threaded order followed by subset in following cases: