# esag.contour: Contour plot (on the plane) of the ESAG and Kent and ESAG... In Directional: A Collection of Functions for Directional Data Analysis

 Contour plot (on the plane) of the ESAG and Kent distributions without any data R Documentation

## Contour plot (on the plane) of the ESAG and Kent and ESAG distributions without any data

### Description

The contour plot (on the plane) of the spherical ESAG and Kent distributions is produced.

### Usage

```esag.contour(mu, gam, lat, long)
kent.contour(k, b)
```

### Arguments

 `k` The concentration parameter. `b` The ovalness parameter. It has to be less than k/2 in order for the distribution to be unimodal. Otherwise it is bimodal. `mu` The mean vector the ESAG distribution, a vector in R^3. `gam` The two gamma parameters of the ESAG distribution. `lat` A positive number determing the range of degrees to move left and right from the latitude center. See the example to better understand this argument. `long` A positive number determing the range of degrees to move up and down from the longitude center. See the example to better understand this argument.

### Details

The goal of this function is for the user to see how the Kent or the SAG distribution looks like.

### Value

A plot containing the contours of the distribution.

### References

Kent John (1982). The Fisher-Bingham distribution on the sphere. Journal of the Royal Statistical Society, Series B, 44(1): 71–80.

Paine P.J., Preston S.P., Tsagris M. and Wood A.T.A. (2018). An Elliptically Symmetric Angular Gaussian Distribution. Statistics and Computing, 28(3):689–697.

```vmf.contour, vmf.kerncontour, spher.esag.contour ```

### Examples

```
kent.contour(10, 4)

mu <- colMeans( as.matrix( iris[,1:3] ) )
gam <- c(1,0.5)
esag.contour(mu, gam, 50, 50)
esag.contour(mu, gam, 30, 40)

```

Directional documentation built on Feb. 16, 2023, 8 p.m.