dwsn {NPCirc}

Wrapped skew-Normal density function

Description

Density function and random generation for the wrapped skew-Normal distribution introduced by Pewsey (2000).

Usage

dwsn(x,xi,eta,lambda,K=NULL,min.k=20)
rwsn(n,xi,eta,lambda)

Arguments

x

Vector of angles where the density is evaluated . The object is coerced to class circular.

n

Number of observations.

xi

Location parameter. The object is coerced to class circular.

eta

Scale parameter.

lambda

Skewness parameter.

K

Number of terms to be used in approximating the density. Default K=NULL.

min.k

Minimum number of terms used in approximating the density.

Details

The NAs will be automatically removed.

Value

dwsn gives the density and rwsn generates random deviates.

Author(s)

Maria Oliveira, Rosa M. Crujeiras and Alberto Rodriguez–Casal

References

Pewsey, A. (2000) The wrapped skew–Normal distribution on the circle. Communications in Statistics - Theory and Methods, 29, 2459–2472.

Examples

set.seed(2012)
# Density function of a wrapped skew-normal distribution WSN(pi,1,20)
wsn <- function(x) dwsn(x, xi=circular(pi), eta=1, lambda=20)
curve.circular(wsn,n=500,xlim=c(-1.65,1.65),main=expression(WSN(pi,1,20)))
# Random generation
data<-rwsn(50,xi=circular(pi),eta=1,lambda=20)
points(data)