

   abline {base}                                R Documentation

   AAdddd aa SSttrraaiigghhtt LLiinnee ttoo aa PPlloott

   DDeessccrriippttiioonn::

        This function adds one or more straight lines through
        the current plot.

   UUssaaggee::

        abline(a, b, ...)
        abline(h=, ...)
        abline(v=, ...)
        abline(untf=, ...)
        abline(coef=, ...)
        abline(reg=, ...)

   DDeettaaiillss::

        The first form 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 contain-
        ing 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 intercept and slope.

        If `untf' is true, and one or both axes are log-trans-
        formed, then a curve is drawn corresponding to a line
        in original coordinates, otherwise a line is drawn in
        the transformed coordinate system. The `h' and `v'
        parameters alway refer to original coordinates.

        The graphical parameters `col' and `lty' can be speci-
        fied as arguments to `abline'; see `par' for details.

   SSeeee AAllssoo::

        `lines' and `segments' for connected and arbitrary
        lines given by their endpoints.  `par'.

   EExxaammpplleess::

        data(cars)
        z <- lm(dist ~ speed, data = cars)
        plot(cars)
        abline(z)

