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)