This is the default panel function for `bwplot`

.

```
panel.bwplot(x, y, box.ratio = 1,
box.width = box.ratio / (1 + box.ratio),
horizontal = TRUE,
pch, col, alpha, cex,
font, fontfamily, fontface,
fill, varwidth = FALSE,
notch = FALSE, notch.frac = 0.5,
…,
levels.fos,
stats = boxplot.stats,
coef = 1.5,
do.out = TRUE,
identifier = "bwplot")
```

x, y

numeric vector or factor. Boxplots drawn for each unique value of
`y`

(`x`

) if `horizontal`

is `TRUE`

(`FALSE`

)

box.ratio

ratio of box thickness to inter box space

box.width

thickness of box in absolute units; overrides
`box.ratio`

. Useful for specifying thickness when the
categorical variable is not a factor, as use of `box.ratio`

alone cannot achieve a thickness greater than 1.

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.

pch, col, alpha, cex, font, fontfamily, fontface

graphical
parameters controlling the dot. `pch="|"`

is treated
specially, by replacing the dot with a line (similar to
`boxplot`

)

fill

color to fill the boxplot

varwidth

logical. If TRUE, widths of boxplots are proportional to the number of points used in creating it.

notch

if `notch`

is `TRUE`

, a notch is drawn in each
side of the boxes. If the notches of two plots do not overlap this
is ‘strong evidence’ that the two medians differ (Chambers et
al., 1983, p. 62). See `boxplot.stats`

for the
calculations used.

notch.frac

numeric in (0,1). When `notch=TRUE`

, the
fraction of the box width that the notches should use.

stats

a function, defaulting to `boxplot.stats`

,
that accepts a numeric vector and returns a list similar to the
return value of `boxplot.stats`

. The function must accept
arguments `coef`

and `do.out`

even if they do not use
them (a `…`

argument is good enough). This function is
used to determine the box and whisker plot.

coef, do.out

passed to `stats`

levels.fos

numeric values corresponding to positions of the factor or shingle variable. For internal use.

…

further arguments, ignored.

identifier

A character string that is prepended to the names of grobs that are created by this panel function.

Creates Box and Whisker plot of `x`

for every level of
`y`

(or the other way round if `horizontal=FALSE`

). By
default, the actual boxplot statistics are calculated using
`boxplot.stats`

. Note that most arguments controlling the
display can be supplied to the high-level `bwplot`

call directly.

Although the graphical parameters for the dot representing the median
can be controlled by optional arguments, many others can not. These
parameters are obtained from the relevant settings parameters
(`"box.rectangle"`

for the box, `"box.umbrella"`

for the
whiskers and `"plot.symbol"`

for the outliers).

# NOT RUN { bwplot(voice.part ~ height, data = singer, xlab = "Height (inches)", panel = function(...) { panel.grid(v = -1, h = 0) panel.bwplot(...) }, par.settings = list(plot.symbol = list(pch = 4))) bwplot(voice.part ~ height, data = singer, xlab = "Height (inches)", notch = TRUE, pch = "|") # }