| abline {base} | R Documentation |
Add a Straight Line to a Plot
Description
This function adds one or more straight lines through the current plot.
The first form above specifies the line in intercept/slope form
(alternatively a can be specified on its own and is taken to
contain the slope and intercept in vector form).
The h= and v= forms draw horizontal and vertical lines
at the specified coordinates.
The coef form specifies the line by a vector containing the
slope and intercept.
reg is a regression object which contains reg$coef. If
it is of length 1 then the value is taken to be the slope of a line
through the origin, otherwise, the first 2 values are taken to be the
slope and intercept.
The graphical parameters col and lty can be specified as
arguments to abline; see par for details.
Usage
abline(a, b, ...)
abline(h=, ...)
abline(v=, ...)
abline(coef=, ...)
abline(reg=, ...)
See Also
lines and segments for connected and
arbitrary lines given by their endpoints.
par.
Examples
data(cars)
z <- lm(dist ~ speed, data = cars)
plot(cars)
abline(z)