Boom (version 0.8)

add.segments: Function to add horizontal line segments to an existing plot

Description

Adds horizontal line segments to an existing plot. The segments are centered at x with height y. The x values are assumed to be equally spaced, so that diff(x) is a constant 'dx'. The line segments go from x +/- half.width.factor *dx, so if half.width.factor=.5 there will be no gaps between segments. The default is to leave a small gap.

This function was originally used to add reference lines to side-by-side boxplots.

Usage

AddSegments(x, y, half.width.factor = 0.45, ...)

Arguments

x

A numeric vector giving the midpoints of the line segments.

y

A numeric vector of the same length as x giving the vertical position of the line segments

half.width.factor

See 'description' above.

…

graphical parameters controlling the type of lines used in the line segments

Value

Called for its side effect.

See Also

boxplot.true

Examples

# NOT RUN {
x <- rnorm(100)
y <- rnorm(100, 1)
boxplot(list(x=x,y=y))
AddSegments(1:2, c(0, 1))  ## add segments to the boxplot

# }