fsort: Fast parallel sort

In Rdatatable/data.table: Extension of `data.frame`

Fast parallel sort

Description

Similar to base::sort but fast using parallelism. Experimental.

Usage

fsort(x, decreasing = FALSE, na.last = FALSE, internal=FALSE, verbose=FALSE, ...)

Arguments

x	A vector. Type double, currently.
decreasing	Decreasing order?
na.last	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.

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:

• data type other than double (numeric)

• data having NAs

• decreasing==FALSE

Value

The input in sorted order.

Examples

x = runif(1e6)
system.time(ans1 <- sort(x, method="quick"))
system.time(ans2 <- fsort(x))
identical(ans1, ans2)

Rdatatable/data.table documentation built on Dec. 21, 2024, 3:08 a.m.