.BG
.VE $Header: /usr/s/current/s/.help/RCS/lines,v 1.5 87/02/04 09:34:08 rab Exp $
.FN lines
.FN points
.TL
lines points: Add Lines or Points to Current Plot
.CS
lines(x, y, type=)
points(x, y, type=, mark=)
.PP
.AG x,y
the co-ordinates for lines or points.  A time-series or
structure containing `x' and `y' may also be given for `x'.
Missing values (NAs) are allowed.
.AG type=
values of "p", "l", "b", "o", "n", and "h" produce points,
lines, both, both (overlaid), nothing, and high-density lines.
Default is "p" for `points', "l" for `lines'.
.AG mark=
An obsolete option for compatibility with old versions.
Now, `pch=' specifies the plotting symbols for a variety of
functions.
Plotting symbols are: square (0); octagon (1); triangle(2);
cross(3); X (4); diamond(5) and inverted triangle(6). To get
superimposed versions of the above use the following
arithmetic(!): 7==0+4; 8==3+4; 9==3+5; 10==1+3; 11==2+6;
12==0+3; 13==1+4; 14==0+2.
Filled-in symbols are square (15); octagon (16); triangle (17);
and diamond (18).
These only work on devices that have polygon-fill capabilities.
.PP
Graphical parameters may also be supplied as arguments to this
function (see `par').
.PP
Data values with an NA in either `x' or `y' are not plotted by
`points'.  Also, `lines' does not draw to or from any such point, thus giving
a break in the line segments.
.PP
If a log scale was specified for either the x- or y-axis, `points' and
`lines' will plot the corresponding values on a log scale.
.SH SEE ALSO
`segments', `arrows', and `symbols'.
.EX
par(usr=c(\-1,15,0,1)) # produce a plot of all the marks
for(i in 0:14){
      points(i,.5,pch=i)
      text(i,.35,i)}
text(7,.75,'Samples of "mark=" Parameter')
.PI
.KW plot*
.KW aplot*
.WR
