| grid.segments {grid} | R Documentation | 
These functions create and draw line segments.
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)
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   | 
name | 
 A character identifier.  | 
gp | 
  An object of class   | 
draw | 
 A logical value indicating whether graphics output should be produced.  | 
vp | 
 A Grid viewport object (or NULL).  | 
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).
A segments grob.  grid.segments returns the value invisibly.
Paul Murrell