R: (Q)uan(Tile)s

qtile {bit64} | R Documentation

## (Q)uan(Tile)s

### Description

Function `prank.integer64` projects the values [min..max] via ranks [1..n] to [0..1]. `qtile.ineger64` is the inverse function of 'prank.integer64' and projects [0..1] to [min..max].

### Usage

    	qtile(x, probs=seq(0, 1, 0.25), ...)
    	## S3 method for class 'integer64'
    qtile(x, probs = seq(0, 1, 0.25), names = TRUE, method = NULL, ...)
    	## S3 method for class 'integer64'
    quantile(x, probs = seq(0, 1, 0.25), na.rm = FALSE, names = TRUE, type=0L, ...)
    	## S3 method for class 'integer64'
    median(x, na.rm = FALSE, ...)
     ## S3 method for class 'integer64'
    mean(x, na.rm = FALSE, ...)
    	## S3 method for class 'integer64'
    summary(object, ...)
     ## mean(x, na.rm = FALSE, ...)
     ## or
     ## mean(x, na.rm = FALSE)

### Arguments

`x` | a integer64 vector
`object` | a integer64 vector
`probs` | numeric vector of probabilities with values in [0,1] - possibly containing `NA`s
`names` | logical; if `TRUE`, the result has a `names` attribute. Set to `FALSE` for speedup with many probs.
`type` | an integer selecting the quantile algorithm, currently only 0 is supported, see details
`method` | NULL for automatic method selection or a suitable low-level method, see details
`na.rm` | logical; if `TRUE`, any `NA` and `NaN`'s are removed from `x` before the quantiles are computed.
`...` | ignored

### Details

Functions `quantile.integer64` with `type=0` and `median.integer64` are convenience wrappers to `qtile`.
Function `qtile` behaves very similar to `quantile.default` with `type=1` in that it only returns existing values, it is mostly symetric but it is using 'round' rather than 'floor'.
Note that this implies that `median.integer64` does not interpolate for even number of values (interpolation would create values that could not be represented as 64-bit integers).
This function automatically chooses from several low-level functions considering the size of `x` and the availability of a cache. Suitable methods are `sortqtl` (fast sorting) and `orderqtl` (memory saving ordering).

### Value

`prank` returns a numeric vector of the same length as `x`.
`qtile` returns a vector with elements from `x` at the relative positions specified by `probs`.

### Author(s)

Jens Oehlschlägel <Jens.Oehlschlaegel@truecluster.com>

### See Also

`rank.integer64` for simple ranks and `quantile` for quantiles.

### Examples

    x <- as.integer64(sample(c(rep(NA, 9), 1:9), 32, TRUE))
    qtile(x, probs=seq(0, 1, 0.25))
    quantile(x, probs=seq(0, 1, 0.25), na.rm=TRUE)
    median(x, na.rm=TRUE)
    summary(x)

    x <- x[!is.na(x)]
    stopifnot(identical(x,  unname(qtile(x, probs=prank(x)))))

[Package bit64 version 4.0.2 Index]