abline(a, b, ...) abline(h=, ...) abline(v=, ...) abline(coef=, ...) abline(reg=, ...)
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.
lines
and segments
for connected and
arbitrary lines given by their endpoints.
par
.data(cars) z <- lm(dist ~ speed, data = cars) plot(cars) abline(z)