R: Default Panel Function for barchart

F_1_panel.barchart {lattice} | R Documentation

## Default Panel Function for barchart

### Description

Default panel function for `barchart`.

### Usage

    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")

### Arguments

`x` | Extent of Bars. By default, bars start at left of panel, unless `origin` is specified, in which case they start there.
`y` | Horizontal location of bars. Possibly a factor.
`box.ratio` | Ratio of bar width to inter-bar space.
`box.width` | 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.
`horizontal` | 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.
`origin` | 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).
`reference` | Logical, whether a reference line is to be drawn at the origin.
`stack` | 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.
`groups` | Optional grouping variable.
`col, border, lty, lwd` | 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.
`identifier` | A character string that is prepended to the names of grobs that are created by this panel function.

### Details

A barchart is drawn in the panel. Note that most arguments controlling the display can be supplied to the high-level `barchart` call directly.

### Author(s)

Deepayan Sarkar Deepayan.Sarkar@R-project.org

### See Also

`barchart`

### Examples

    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)))

[Package lattice version 0.20-6 Index]