This function computes a `beatSpectrum`

and calculates some basic
measurements of its complexity. The complexity value is calculated as the
maximum identified repeating period (in seconds) divided by the number of
peaks.

## Usage

`beatComplexity(wave, plot = FALSE)`

## Arguments

- wave
A Wave object

- plot
If TRUE a spectrogram overlaid with the peaks is plotted.

## Value

A list of the complexity, a vector of the peak periods, and the number of peaks.

## Examples

```
if (FALSE) {
beatComplexity(sheep)
beatComplexity(sheep, plot=TRUE)
}
```