plot.formula {graphics} | R Documentation |
Specify a scatterplot or add points or lines via a formula.
## S3 method for class 'formula': plot(formula, data = parent.frame(), ..., subset, ylab = varnames[response], ask = TRUE) ## S3 method for class 'formula': points(formula, data = parent.frame(), ..., subset) ## S3 method for class 'formula': lines(formula, data = parent.frame(), ..., subset)
formula |
a formula , such as y ~ x . |
data |
a data.frame (or list) from which the variables in
formula should be taken. |
... |
Arguments to be passed to or from other methods.
horizontal = TRUE is also accepted. |
subset |
an optional vector specifying a subset of observations to be used in the fitting process. |
ylab |
the y label of the plot(s). |
ask |
logical, see par . |
Both the terms in the formula and the ...
arguments are
evaluated in data
enclosed in parent.frame()
if
data
is a list or a data frame. The terms of the formula and
those arguments in ...
that are of the same length as
data
are subjected to the subsetting specified in
subset
. If the formula in plot.formula
contains more
than one non-response term, a series of plots of y against each term
is given. A plot against the running index can be specified as
plot(y ~ 1)
.
Missing values are not considered in these methods, and in particular cases with missing values are not removed.
If y
is an object (i.e. has a class
attribute)
then plot.formula
looks for a plot method for that class first.
Otherwise, the class of x
will determine the type of the plot.
For factors this will be a parallel boxplot, and argument
horizontal = TRUE
can be used (see boxplot
).
These functions are invoked for their side effect of drawing in the active graphics device.
plot.default
, points
, lines
,
plot.factor
.
op <- par(mfrow=c(2,1)) plot(Ozone ~ Wind, data = airquality, pch=as.character(Month)) plot(Ozone ~ Wind, data = airquality, pch=as.character(Month), subset = Month != 7) par(op)