lattice (version 0.19-30)

F_2_panel.functions: Useful Panel Function Components

Description

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

Usage

panel.abline(a = NULL, b = 0,
             h = NULL, v = NULL,
             reg = NULL, coef = NULL,
             col, col.line, lty, lwd, alpha, type,
             ...,
             reference = FALSE,
             identifier = "abline")
panel.refline(...) 
panel.curve(expr, from, to, n = 101,
            curve.type = "l",
            col, lty, lwd, type,
            ...,
            identifier = "curve")
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, col.line, lty, lwd, alpha,
          ...,
          identifier = "rug")
panel.average(x, y, fun = mean, horizontal = TRUE,
              lwd, lty, col, col.line, type,
              ...,
              identifier = "linejoin")
panel.linejoin(x, y, fun = mean, horizontal = TRUE,
               lwd, lty, col, col.line, type,
               ...,
               identifier = "linejoin")panel.fill(col, border, ..., identifier = "fill")
panel.grid(h=3, v=3, col, col.line, lty, lwd, x, y, ..., identifier = "grid")
panel.lmline(x, y, ..., identifier = "lmline")
panel.mathdensity(dmath = dnorm, args = list(mean=0, sd=1),
                  n = 50, col, col.line, lwd, lty, type,
                  ..., identifier = "mathdensity")

Details

panel.abline adds a line of the form y = a + b * x, or vertical and/or horizontal lines. Graphical parameters are obtained from the add.line settings by default. panel.refline is similar, but uses the reference.line settings for the defaults.

panel.grid draws a reference grid.

panel.curve adds a curve, similar to what curve does with add = TRUE. Graphical parameters for the curve are obtained from the add.line setting.

panel.average 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.

panel.linejoin is an alias for panel.average. It is retained for back-compatibility, and may go away in future.

panel.mathdensity plots a (usually theoretical) probability density function. This can be useful in conjunction with histogram and densityplot to visually assess 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)).

See Also

Lattice, panel.axis, panel.identify identify, trellis.par.set.

Examples

## Interaction Plot

bwplot(yield ~ site, barley, groups = year,
       panel = function(x, y, groups, subscripts, ...) {
           panel.grid(h = -1, v = 0)
           panel.stripplot(x, y, ..., jitter.data = TRUE,
                           groups = groups, subscripts = subscripts)
           panel.superpose(x, y, ..., panel.groups = panel.average,
                           groups = groups, subscripts = subscripts)
       },
       auto.key =
       list(points = FALSE, lines = TRUE, columns = 2))

## Superposing a fitted normal density on a Histogram

histogram( ~ height | voice.part, data = singer, layout = c(2, 4),
          type = "density", border = "transparent", col.line = "grey60",
          xlab = "Height (inches)",
          ylab = "Density Histogram
 with Normal Fit",
          panel = function(x, ...) {
              panel.histogram(x, ...)
              panel.mathdensity(dmath = dnorm,
                                args = list(mean=mean(x),sd=sd(x)), ...)
          } )