R: Useful Panel Functions

panel.functions {lattice}

R Documentation

Useful Panel Functions

Description

These are predefined panel functions available in lattice for use in constructing new panel functions (usually on-the-fly).

Usage

panel.abline(a, b, ...)
panel.abline(coef, ...)
panel.abline(reg, ...)
panel.abline(h= ,v= , ...)
panel.curve(expr, from, to, n = 101,
            curve.type = "l", ...)
panel.rug(x = NULL, y = NULL,
          regular = TRUE, start, end, ...)
panel.fill(col="grey", ...)
panel.grid(h=3, v=3, ...)
panel.lmline(x,y,...) = panel.abline(lm(y~x),...)
panel.loess(x, y, span = 2/3, degree = 1,
            family = c("symmetric", "gaussian"),
            evaluation = 50, ...)
panel.linejoin(x, y, fun = mean, horizontal = TRUE, ...)
panel.mathdensity(dmath = dnorm, args = list(mean=0, sd=1))
panel.axis(side = 1:4, at,
           labels = TRUE, tick = TRUE,
           half = TRUE, which.half = c("lower", "upper", "upper","lower"),
           tck = 1, rot)

Arguments

`x, y`	variables defining the contents of the panel
`a, b`	Coefficients of the line to be added
`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, numerical vectors giving y and x locations respectively of horizontal and vertical lines to be added to the plot. For panel.grid, number of horizontal and vertical reference lines to be added to the plot; h=-1 and v=-1 make the grids aligned with the axis labels (this doesn't always work).
`expr`	expression as a function of x or a function to plot as a curve
`regular`	logical indicating whether `rug' 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
`from, to`	optional lower and upper x-limits of curve. If missing, limits of current panel are used
`n`	number of points to use for drawing the curve
`curve.type`	type of curve ('p' for points, etc), passed to `llines`
`col`	color
`span, degree, family, evaluation`	arguments to `loess.smooth` in the `modreg` library. `panel.loess` is essentially a wrapper on `loess.smooth`
`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
`side`	subset of 1:4, indicating which side which
`at`	location of labels. No default.
`labels`	logical indicating whether labels are to be drawn, or the labels to go along with `at`
`tick`	logical, whether to draw ticks
`half`	logical, whether only half of scales will be drawn for each side
`which.half`	character vector of length 4 (recycled if necessary), each being either ``lower'' or ``upper''. Indicates which half is to be used for tick locations if `half = TRUE`, for sides 1 to 4
`tck`	numeric scalar, tick length
`rot`	numeric 4-vector (recycled if necessary), rotation angles for sides 1 to 4
`...`	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.

Details

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. Can be useful in conjunction with histogram and densityplot to visually estimate goodness of fit.

panel.axis draws axis tick marks INSIDE a panel. It honours the (native) axis scales within the panel, but the locations need to be explicitly specified. Used in panel.pairs for splom.

Author(s)