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Plots a Ford (battleship curve) diagram.

Usage

plot_ford(object, ...)

# S4 method for matrix
plot_ford(
  object,
  weights = FALSE,
  EPPM = FALSE,
  fill = "darkgrey",
  border = NA,
  axes = TRUE,
  ...
)

# S4 method for data.frame
plot_ford(
  object,
  weights = FALSE,
  EPPM = FALSE,
  fill = "darkgrey",
  border = NA,
  axes = TRUE,
  ...
)

Arguments

object

A \(m \times p\) numeric matrix or data.frame of count data (absolute frequencies giving the number of individuals for each category, i.e. a contingency table).

...

Currently not used.

weights

A logical scalar: should the row sums be displayed?

EPPM

A logical scalar: should the EPPM be drawn? See seriograph().

fill

The color for filling the bars.

border

The color to draw the borders.

axes

A logical scalar: should axes be drawn on the plot? It will omit labels where they would abut or overlap previously drawn labels.

Value

plot_ford() is called for its side-effects: it results in a graphic being displayed (invisibly returns object).

References

Ford, J. A. (1962). A quantitative method for deriving cultural chronology. Washington, DC: Pan American Union. Technical manual 1.

Author

N. Frerebeau

Examples

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

## Plot a Ford diagram
plot_ford(mississippi)


plot_ford(mississippi, weights = TRUE)