ramsort.integer64: Low-level intger64 methods for in-RAM sorting and ordering

Description

Fast low-level methods for sorting and ordering. The ..sortorder methods do sorting and ordering at once, which requires more RAM than ordering but is (almost) as fast as as sorting.

Usage

# S3 method for integer64
shellsort(x, has.na=TRUE, na.last=FALSE, decreasing=FALSE, ...)
# S3 method for integer64
shellsortorder(x, i, has.na=TRUE, na.last=FALSE, decreasing=FALSE, ...)
# S3 method for integer64
shellorder(x, i, has.na=TRUE, na.last=FALSE, decreasing=FALSE, ...)
# S3 method for integer64
mergesort(x, has.na=TRUE, na.last=FALSE, decreasing=FALSE, ...)
# S3 method for integer64
mergeorder(x, i, has.na=TRUE, na.last=FALSE, decreasing=FALSE, ...)
# S3 method for integer64
mergesortorder(x, i, has.na=TRUE, na.last=FALSE, decreasing=FALSE, ...)
# S3 method for integer64
quicksort(x, has.na=TRUE, na.last=FALSE, decreasing=FALSE
, restlevel=floor(1.5*log2(length(x))), ...)
# S3 method for integer64
quicksortorder(x, i, has.na=TRUE, na.last=FALSE, decreasing=FALSE
, restlevel=floor(1.5*log2(length(x))), ...)
# S3 method for integer64
quickorder(x, i, has.na=TRUE, na.last=FALSE, decreasing=FALSE
, restlevel=floor(1.5*log2(length(x))), ...)
# S3 method for integer64
radixsort(x, has.na=TRUE, na.last=FALSE, decreasing=FALSE, radixbits=8L, ...)
# S3 method for integer64
radixsortorder(x, i, has.na=TRUE, na.last=FALSE, decreasing=FALSE, radixbits=8L, ...)
# S3 method for integer64
radixorder(x, i, has.na=TRUE, na.last=FALSE, decreasing=FALSE, radixbits=8L, ...)
# S3 method for integer64
ramsort(x, has.na = TRUE, na.last=FALSE, decreasing = FALSE, stable = TRUE
, optimize = c("time", "memory"), VERBOSE = FALSE, ...)
# S3 method for integer64
ramsortorder(x, i, has.na = TRUE, na.last=FALSE, decreasing = FALSE, stable = TRUE
, optimize = c("time", "memory"), VERBOSE = FALSE, ...)
# S3 method for integer64
ramorder(x, i, has.na = TRUE, na.last=FALSE, decreasing = FALSE, stable = TRUE
, optimize = c("time", "memory"), VERBOSE = FALSE, ...)

Value

These functions return the number of NAs found or assumed during sorting

Arguments

x: a vector to be sorted by ramsort.integer64 and ramsortorder.integer64, i.e. the output of sort.integer64
i: integer positions to be modified by ramorder.integer64 and ramsortorder.integer64, default is 1:n, in this case the output is similar to order.integer64
has.na: boolean scalar defining whether the input vector might contain NAs. If we know we don't have NAs, this may speed-up. Note that you risk a crash if there are unexpected NAs with has.na=FALSE
na.last: boolean scalar telling ramsort whether to sort NAs last or first. Note that 'boolean' means that there is no third option NA as in sort
decreasing: boolean scalar telling ramsort whether to sort increasing or decreasing
stable: boolean scalar defining whether stable sorting is needed. Allowing non-stable may speed-up.
optimize: by default ramsort optimizes for 'time' which requires more RAM, set to 'memory' to minimize RAM requirements and sacrifice speed
restlevel: number of remaining recursionlevels before quicksort switches from recursing to shellsort
radixbits: size of radix in bits
VERBOSE: cat some info about chosen method
...: further arguments, passed from generics, ignored in methods

Author

Jens Oehlschlägel <Jens.Oehlschlaegel@truecluster.com>

Details

see ramsort

Examples

Run this code

  x <- as.integer64(sample(c(rep(NA, 9), 1:9), 32, TRUE))
  x
  message("ramsort example")
  s <- clone(x)
  ramsort(s)
  message("s has been changed in-place - whether or not ramsort uses an in-place algorithm")
  s
  message("ramorder example")
  s <- clone(x)
  o <- seq_along(s)
  ramorder(s, o)
  message("o has been changed in-place - s remains unchanged")
  s
  o
  s[o]
  message("ramsortorder example")
  o <- seq_along(s)
  ramsortorder(s, o)
  message("s and o have both been changed in-place - this is much faster")
  s
  o

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