panel.functions {lattice}  R Documentation 
These are predefined panel functions available in lattice for use in constructing new panel functions (usually onthefly).
panel.abline(a = NULL, b = 0, h = NULL, v = NULL, reg = NULL, coef = NULL, col, col.line, lty, lwd, type, ...) panel.curve(expr, from, to, n = 101, curve.type = "l", col, lty, lwd, type, ...) panel.rug(x = NULL, y = NULL, regular = TRUE, start = if (regular) 0 else 0.97, end = if (regular) 0.03 else 1, x.units = rep("npc", 2), y.units = rep("npc", 2), col, lty, lwd, alpha, ...) panel.linejoin(x, y, fun = mean, horizontal = TRUE, lwd, lty, col, col.line, type, ...) panel.fill(col, border, ...) panel.grid(h=3, v=3, col, col.line, lty, lwd, ...) panel.lmline(x, y, ...) panel.loess(x, y, span = 2/3, degree = 1, family = c("symmetric", "gaussian"), evaluation = 50, lwd, lty, col, col.line, type, ...) panel.mathdensity(dmath = dnorm, args = list(mean=0, sd=1), n = 50, col, col.line, lwd, lty, type, ...)
x, y 
variables defining the contents of the panel 
a, b 
Coefficients of the line to be added by
panel.abline . a can be a vector of length 2,
representing the coefficients of the line to be added, in which case
b should be missing. a can also be an appropriate
‘regression’ object, i.e., an object which has a
coef method that returns a length 2 numeric vector.
The corresponding line will be plotted. The reg argument
will override a if specified.

coef 
Coefficients of the line to be added as a length 2 vector 
reg 
A regression object. The corresponding fitted line will be drawn 
h, v 
For panel.abline , these are numeric vectors giving
locations respectively of horizontal and vertical lines to be added
to the plot, in native coordinates. For panel.grid , these
usually specify the number of horizontal and vertical reference
lines to be added to the plot. Alternatively, they can be negative
numbers. h=1 and v=1 are intended to make the grids
aligned with the axis labels. This doesn't always work; all that
actually happens is that the locations are chosen using
pretty , which is also how the label positions are chosen in
the most common cases (but not for factor or datetime variables,
for instance). h and v can be negative numbers other
than 1 , in which case h and v (as
appropriate) is supplied as the n argument to
pretty . 
expr 
expression as a function of x or a function to plot as a curve 
n 
the number of points to use for drawing the curve 
regular 
logical indicating whether the ‘rug’ is to be drawn on the regular side (left / bottom) or not (right / top) 
start, end 
endpoints of rug segments, in normalized parent coordinates (between 0 and 1). Defaults depend on value of regular, and cover 3% of the panel width and height 
x.units, y.units 
character vector, replicated to be of length two. Specifies the
(grid) units associated with start and end above.
x.units and y.units are for the rug on the xaxis and
yaxis respectively (and thus are associated with start and
end values on the y and x scales respectively).

from, to 
optional lower and upper xlimits of curve. If missing, limits of current panel are used 
curve.type 
type of curve ("p" for points, etc), passed
to llines

col, col.line, lty, lwd, alpha, border 
graphical parameters 
type 
usually ignored. This is present only to make sure an
explicitly specified type argument (perhaps meant for another
function) doesn't affect the display. 
span, degree, family, evaluation 
arguments to
loess.smooth , for which panel.loess is essentially
a wrapper

fun 
the function that will be applied to the subset of x(y) determined by the unique values of y(x) 
horizontal 
logical. If FALSE, the plot is ‘transposed’
in the sense that the behaviours of x and y are switched. x is now
the ‘factor’. Interpretation of other arguments change
accordingly. See documentation of bwplot for a fuller
explanation.

dmath 
A vectorized function that produces density values
given a numeric vector named x , e.g., dnorm 
args 
list giving additional arguments to be passed to dmath 
... 
graphical parameters can be supplied. see function
definition for details. Color can usually be specified by
col , col.line and col.symbol , the last two
overriding the first for lines and points respectively.

panel.abline
adds a line of the form y=a+bx
or vertical
and/or horizontal lines. Graphical parameters are obtained from
reference.line
for panel.grid, and add.line
for the
others (can be set using trellis.par.set
)
panel.curve
adds a curve, similar to what curve
does
with add = TRUE
. Graphical parameters for the line are obtained
from the add.line
setting.
panel.linejoin
treats one of x and y as a factor (according to
the value of horizontal
), calculates fun
applied to the
subsets of the other variable determined by each unique value of the
factor, and joins them by a line. Can be used in conjunction with
panel.xyplot
and more commonly with panel.superpose to produce
interaction plots. See xyplot
documentation for an
example.
panel.mathdensity
plots a (usually theoretical) probability
density function. This can be useful in conjunction with
histogram
and densityplot
to visually estimate goodness
of fit (note, however, that qqmath
is more suitable for this).
panel.rug
adds a rug representation of the (marginal)
data to the panel, much like rug
.
panel.lmline(x, y)
is equivalent to
panel.abline(lm(y~x))
.
Deepayan Sarkar Deepayan.Sarkar@Rproject.org
loess.smooth
,
panel.axis
, panel.identify
identify
, trellis.par.get