byf.hist {RVAideMemoire}

Histogram for factor levels

Description

Draws a histogram of a numeric variable per level of a factor.

Usage

byf.hist(formula, data, sep = FALSE, density = TRUE, xlab = NULL, ylab = NULL,
  col = NULL)

Arguments

formula

a formula of the form a ~ b where a gives the data values and b a factor giving the corresponding groups.

data

an optional data frame containing the variables in the formula formula. By default the variables are taken from environment(formula).

sep

logical. If TRUE a histogram is displayed per level of the factor. If FALSE all levels are displayed on the same histogram.

density

logical. If TRUE density polygons are displayed, if FALSE classical counts are displayed.

xlab

label for x-axis (name of the response variable as default).

ylab

label for y-axis ("Density" or "Frequency" as default, depending on the type of histogram).

col

color(s) used for density curves or bars.

Author(s)

Maxime HERVE <[e-mail]>

See Also

hist

Examples

data(iris)
byf.hist(Sepal.Length~Species,data=iris)