Compositional (version 4.1)

Contour plot of a Dirichlet distribution in S^2: Contour plot of a Dirichlet distribution in \(S^2\)

Description

Contour plot of a Dirichlet distribution in \(S^2\).

Usage

diri.contour(a, n = 100, x = NULL)

Arguments

a

A vector with three elements corresponding to the 3 (estimated) parameters.

n

The number of grid points to consider over which the density is calculated.

x

This is either NULL (no data) or contains a 3 column matrix with compositional data.

Value

A ternary diagram with the points and the Dirichlet contour lines.

Details

The user can plot only the contour lines of a Dirichlet with a given vector of parameters, or can also add the relevant data should he/she wish to.

References

Ng Kai Wang, Guo-Liang Tian and Man-Lai Tang (2011). Dirichlet and related distributions: Theory, methods and applications. John Wiley \& Sons.

Aitchison J. (1986). The statistical analysis of compositional data. Chapman \& Hall.

See Also

norm.contour, bivt.contour, comp.kerncontour, mixnorm.contour

Examples

# NOT RUN {
x <- as.matrix( iris[, 1:3] )
x <- x / rowSums(x)
diri.contour( a = c(3, 4, 2) )
# }