Computes and draws a confidence/tolerance ellipse.

## Usage

```
ternary_ellipse(x, y, z, ...)
ternary_confidence(x, y, z, ...)
ternary_tolerance(x, y, z, ...)
# S4 method for numeric,numeric,numeric
ternary_ellipse(x, y, z, radius = 1, ...)
# S4 method for ANY,missing,missing
ternary_ellipse(x, radius = 1, ...)
# S4 method for numeric,numeric,numeric
ternary_confidence(x, y, z, level = 0.95, ...)
# S4 method for ANY,missing,missing
ternary_confidence(x, level = 0.95, ...)
# S4 method for numeric,numeric,numeric
ternary_tolerance(x, y, z, level = 0.95, ...)
# S4 method for ANY,missing,missing
ternary_tolerance(x, level = 0.95, ...)
```

## Arguments

- x, y, z
A

`numeric`

vector giving the x, y and z ternary coordinates of a set of points. If`y`

and`z`

are missing, an attempt is made to interpret`x`

in a suitable way (see`grDevices::xyz.coords()`

).- ...
Further arguments to be passed to

`graphics::polygon()`

.- radius
A

`numeric`

vector specifying the scaling of the half-diameters.- level
A

`numeric`

vector specifying the confidence/tolerance level.

## Details

Ellipse coordinates are computed after an isometric log ratio transformation of the original data.

## See also

Other statistics:
`ternary_contour()`

,
`ternary_density()`

,
`ternary_hull()`

,
`ternary_mean()`

,
`ternary_pca()`

## Examples

```
## Ellipses
## Data from Aitchison 1986
ternary_plot(lava, panel.first = ternary_grid(5, 10))
ternary_tolerance(lava, level = 0.95, border = "blue", lty = 2)
ternary_confidence(lava, level = 0.95, border = "red", lty = 3)
```