panel.functions           package: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):

     Deepayan Sarkar deepayan@stat.wisc.edu

See Also:

     'loess.smooth', 'trellis.par.get'

