R: Draw Line Segments

grid.segments {grid}

R Documentation

Draw Line Segments

Description

These functions create and draw line segments.

Usage

grid.segments(x0 = unit(0, "npc"), y0 = unit(0, "npc"),
              x1 = unit(1, "npc"), y1 = unit(1, "npc"),
              default.units = "npc",
              arrow = NULL,
              name = NULL, gp = gpar(), draw = TRUE, vp = NULL)
segmentsGrob(x0 = unit(0, "npc"), y0 = unit(0, "npc"),
              x1 = unit(1, "npc"), y1 = unit(1, "npc"),
              default.units = "npc",
              arrow = NULL, name = NULL, gp = gpar(), vp = NULL)

Arguments

x0

Numeric indicating the starting x-values of the line segments.

y0

Numeric indicating the starting y-values of the line segments.

x1

Numeric indicating the stopping x-values of the line segments.

y1

Numeric indicating the stopping y-values of the line segments.

default.units

A string.

arrow

A list describing arrow heads to place at either end of the line segments, as produced by the arrow function.

name

A character identifier.

gp

An object of class "gpar", typically the output from a call to the function gpar. This is basically a list of graphical parameter settings.

draw

A logical value indicating whether graphics output should be produced.

vp

A Grid viewport object (or NULL).

Details

Both functions create a segments grob (a graphical object describing segments), but only grid.segments draws the segments (and then only if draw is TRUE).

Value

A segments grob. grid.segments returns the value invisibly.

Author(s)

Paul Murrell