Plots a Bertin diagram.

## Usage

plot_bertin(object, ...)

# S4 method for matrix
plot_bertin(object, threshold = NULL, scale = NULL)

# S4 method for data.frame
plot_bertin(object, threshold = NULL, scale = NULL)

## Arguments

object

A $$m \times p$$ numeric matrix or data.frame of count data (absolute frequencies giving the number of individuals for each class).

...

Currently not used.

threshold

A function that takes a numeric vector as argument and returns a numeric threshold value (see below). If NULL (the default), no threshold is computed.

scale

A function used to scale each variable, that takes a numeric vector as argument and returns a numeric vector. If NULL (the default), no scaling is performed.

## Value

A ggplot2::ggplot object.

## Bertin Matrix

As de Falguerolles et al. (1997) points out: "In abstract terms, a Bertin matrix is a matrix of displays. ... To fix ideas, think of a data matrix, variable by case, with real valued variables. For each variable, draw a bar chart of variable value by case. High-light all bars representing a value above some sample threshold for that variable."

## References

Bertin, J. (1977). La graphique et le traitement graphique de l'information. Paris: Flammarion. Nouvelle Bibliothèque Scientifique.

de Falguerolles, A., Friedrich, F. & Sawitzki, G. (1997). A Tribute to J. Bertin's Graphical Data Analysis. In W. Badilla & F. Faulbaum (eds.), SoftStat '97: Advances in Statistical Software 6. Stuttgart: Lucius & Lucius, p. 11-20.

Other plot methods: matrigraph(), plot_diceleraas(), plot_diversity, plot_ford(), plot_heatmap(), plot_rank(), plot_spot(), seriograph()

N. Frerebeau

## Examples

## Data from Lipo et al. 2015
data("mississippi", package = "folio")

## Plot a Bertin diagram...
## ...without threshold
plot_bertin(mississippi)

## ...with variables scaled to 0-1 and the variable mean as threshold
scale_01 <- function(x) (x - min(x)) / (max(x) - min(x))
plot_bertin(mississippi, threshold = mean, scale = scale_01)