statip: densityfun – R documentation

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densityfun

Kernel density estimation

Description

Return a function performing kernel density estimation. The difference between density and densityfun is similar to that between approx and approxfun.

Usage

densityfun(
  x,
  bw = "nrd0",
  adjust = 1,
  kernel = "gaussian",
  weights = NULL,
  window = kernel,
  width,
  n = 512,
  from,
  to,
  cut = 3,
  na.rm = FALSE,
  ...
)

Arguments

`x`	numeric. The data from which the estimate is to be computed.
`bw`	numeric. The smoothing bandwidth to be used. See the eponymous argument of `density`.
`adjust`	numeric. The bandwidth used is actually `adjust*bw`. This makes it easy to specify values like 'half the default' bandwidth.
`kernel, window`	character. A string giving the smoothing kernel to be used. Authorized kernels are listed in `.kernelsList()`. See also the eponymous argument of `density`.
`weights`	numeric. A vector of non-negative observation weights, hence of same length as `x`. See the eponymous argument of `density`.
`width`	this exists for compatibility with S; if given, and `bw` is not, will set `bw` to `width` if this is a character string, or to a kernel-dependent multiple of `width` if this is numeric.
`n`	The number of equally spaced points at which the density is to be estimated. See the eponymous argument of `density`.
`from, to`	The left and right-most points of the grid at which the density is to be estimated; the defaults are `cut * bw` outside of `range(x)`.
`cut`	By default, the values of `from` and `to` are cut bandwidths beyond the extremes of the data. This allows the estimated density to drop to approximately zero at the extremes.
`na.rm`	logical. If `TRUE`, missing values are removed from `x`. If `FALSE` any missing values cause an error.
`...`	Additional arguments for (non-default) methods.

Value

A function that can be called to generate a density.

Author(s)

Adapted from the density function of package stats. The C code of BinDist is copied from package stats and authored by the R Core Team with contributions from Adrian Baddeley.

Examples

x <- rlnorm(1000, 1, 1)
f <- densityfun(x, from = 0)
curve(f(x), xlim = c(0, 20))

statip

Statistical Functions for Probability Distributions and Regression

v0.2.3

GPL-3

Authors

Paul Poncet [aut, cre], The R Core Team [aut, cph] (C function 'BinDist' copied from package 'stats'), The R Foundation [cph] (C function 'BinDist' copied from package 'stats'), Adrian Baddeley [ctb] (C function 'BinDist' copied from package 'stats')

Initial release