densityplot
Kernel Probability Density Plots
Draw Kernel Density plots
- Keywords
- hplot
Usage
densityplot(formula, data, n = 50, plot.points = TRUE, ref = FALSE, ...)
Arguments
- formula
- A formula of the form
~ x | g1 * g2 * ...
indicating that density plots ofx
should be produced conditional on the levels of the variablesg1,g2,...
.x
must be numeric, and each of - data
- data frame in which variables are to be evaluated.
- n
- number of points at which density is to be evaluated
- plot.points
- logical specifying whether the
x
values should be plotted. - ref
- logical specifying whether a reference x-axis should be drawn.
- ...
- arguments to be passed down to the panel function, in
turn to be passed to
density
(if the default panel function is used).
Details
See the documentation for trellis.args
for description of other
valid arguments. The density estimate is actually calculated using the
function density
, and all arguments accepted by it can be
passed (as ...
) in the call to densityplot
to control
the output. See documentation of density
for details. (Note: The
default value of the argument n
of density
is changed to
50.)
Value
- An object of class ``trellis'', plotted by default by
print.trellis
.
synopsis
densityplot(formula, data = parent.frame(), aspect = "fill", layout = NULL, panel = panel.densityplot, prepanel = NULL, scales = list(), strip = TRUE, groups = NULL, xlab, xlim, ylab, ylim, bw = NULL, adjust = NULL, kernel = NULL, window = NULL, width = NULL, give.Rkern = FALSE, n = 50, from = NULL, to = NULL, cut = NULL, na.rm = NULL, ..., subscripts = !is.null(groups), subset = TRUE)
See Also
trellis.args
, density
,
panel.densityplot
,
panel.mathdensity
,Lattice
Examples
data(singer)
densityplot( ~ height | voice.part, data = singer, layout = c(2, 4),
xlab = "Height (inches)", bw = 5)
## Using a predefined panel function to fit a normal distribution
densityplot( ~ height | voice.part, data = singer, layout = c(2, 4),
xlab = "Height (inches)",
ylab = "Kernel Density/ Normal Fit",
main = list("Estimated Density", cex = 2, col = "DarkOliveGreen"),
panel = function(x, ...) {
panel.xyplot(x = jitter(x),
y = rep(0, length(x)))
panel.densityplot(x, ...)
panel.mathdensity(dmath = dnorm,
args = list(mean=mean(x),sd=sd(x)))
} )