Default panel function for barchart
.
panel.barchart(x, y, box.ratio = 1, box.width,
horizontal = TRUE,
origin = NULL, reference = TRUE,
stack = FALSE,
groups = NULL,
col = if (is.null(groups)) plot.polygon$col
else superpose.polygon$col,
border = if (is.null(groups)) plot.polygon$border
else superpose.polygon$border,
lty = if (is.null(groups)) plot.polygon$lty
else superpose.polygon$lty,
lwd = if (is.null(groups)) plot.polygon$lwd
else superpose.polygon$lwd,
…, identifier = "barchart")
Extent of Bars. By default, bars start at left of panel,
unless origin
is specified, in which case they start there.
Horizontal location of bars. Possibly a factor.
Ratio of bar width to inter-bar space.
Thickness of bars 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.
Logical flag. 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.
The origin for the bars. For grouped displays with
stack = TRUE
, this argument is ignored and the origin set to
0. Otherwise, defaults to NULL
, in which case bars start at
the left (or bottom) end of a panel. This choice is somewhat
unfortuntate, as it can be misleading, but is the default for
historical reasons. For tabular (or similar) data, origin =
0
is usually more appropriate; if not, one should reconsider the
use of a bar chart in the first place (dot plots are often a good
alternative).
Logical, whether a reference line is to be drawn at the origin.
logical, relevant when groups is non-null. If
FALSE
(the default), bars for different values of the
grouping variable are drawn side by side, otherwise they are
stacked.
Optional grouping variable.
Graphical parameters for the bars. By default, the trellis parameter
plot.polygon
is used if there is no grouping variable, otherwise
superpose.polygon
is used. col
gives the fill color,
border
the border color, and lty
and lwd
the
line type and width of the borders.
Extra arguments will be accepted but ignored.
A character string that is prepended to the names of grobs that are created by this panel function.
A barchart is drawn in the panel. Note that most arguments controlling
the display can be supplied to the high-level barchart
call
directly.
# NOT RUN {
barchart(yield ~ variety | site, data = barley,
groups = year, layout = c(1,6), origin = 0,
ylab = "Barley Yield (bushels/acre)",
scales = list(x = list(abbreviate = TRUE,
minlength = 5)))
# }
Run the code above in your browser using DataLab