Cauchy
The Cauchy Distribution
Density, distribution function, quantile function and random
generation for the Cauchy distribution with location parameter
location
and scale parameter scale
.
- Keywords
- distribution
Usage
dcauchy(x, location = 0, scale = 1, log = FALSE)
pcauchy(q, location = 0, scale = 1, lower.tail = TRUE, log.p = FALSE)
qcauchy(p, location = 0, scale = 1, lower.tail = TRUE, log.p = FALSE)
rcauchy(n, location = 0, scale = 1)
Arguments
- x, q
- vector of quantiles.
- p
- vector of probabilities.
- n
- number of observations. If
length(n) > 1
, the length is taken to be the number required. - location, scale
- location and scale parameters.
- log, log.p
- logical; if TRUE, probabilities p are given as log(p).
- lower.tail
- logical; if TRUE (default), probabilities are $P[X \le x]$, otherwise, $P[X > x]$.
Details
If location
or scale
are not specified, they assume
the default values of 0
and 1
respectively.
The Cauchy distribution with location $l$ and scale $s$ has density $$f(x) = \frac{1}{\pi s} \left( 1 + \left(\frac{x - l}{s}\right)^2 \right)^{-1}% $$ for all $x$.
Value
dcauchy
, pcauchy
, and qcauchy
are respectively
the density, distribution function and quantile function of the Cauchy
distribution. rcauchy
generates random deviates from the
Cauchy.The length of the result is determined by n
for
rcauchy
, and is the maximum of the lengths of the
numerical arguments for the other functions.The numerical arguments other than n
are recycled to the
length of the result. Only the first elements of the logical
arguments are used.
Source
dcauchy
, pcauchy
and qcauchy
are all calculated
from numerically stable versions of the definitions. rcauchy
uses inversion.
References
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
Johnson, N. L., Kotz, S. and Balakrishnan, N. (1995) Continuous Univariate Distributions, volume 1, chapter 16. Wiley, New York.
See Also
Distributions for other standard distributions, including
dt
for the t distribution which generalizes
dcauchy(*, l = 0, s = 1)
.
Examples
library(stats)
dcauchy(-1:4)