R: Panel Function for Display Marked by groups

F_2_panel.superpose {lattice} | R Documentation

## Panel Function for Display Marked by groups

### Description

These are panel functions for Trellis displays useful when a grouping variable is specified for use within panels. The `x` (and `y` where appropriate) variables are plotted with different graphical parameters for each distinct value of the grouping variable.

### Usage

    panel.superpose(x, y = NULL, subscripts, groups,
                    panel.groups = "panel.xyplot",
                    ...,
                    col, col.line, col.symbol,
                    pch, cex, fill, font,
                    fontface, fontfamily,
                    lty, lwd, alpha,
                    type = "p", grid = FALSE,
                    distribute.type = FALSE)
    panel.superpose.2(..., distribute.type = TRUE)

    panel.superpose.plain(...,
                          col, col.line, col.symbol,
                          pch, cex, fill, font,
                          fontface, fontfamily,
                          lty, lwd, alpha)

### Arguments

`x,y` | Coordinates of the points to be displayed. Usually numeric.
`panel.groups` | The panel function to be used for each subgroup of points. Defaults to `panel.xyplot`. To be able to distinguish between different levels of the originating group inside `panel.groups`, it will be supplied two special arguments called `group.number` and `group.value` which will hold the numeric code and factor level corresponding to the current level of `groups`. No special care needs to be taken when writing a `panel.groups` function if this feature is not used.
`subscripts` | An integer vector of subscripts giving indices of the `x` and `y` values in the original data source. See the corresponding entry in `xyplot` for details.
`groups` | A grouping variable. Different graphical parameters will be used to plot the subsets of observations given by each distinct value of `groups`. The default graphical parameters are obtained from the `"superpose.symbol"` and `"superpose.line"` settings using `trellis.par.get` wherever appropriate.
`type` | Usually a character vector specifying how each group should be drawn. Formally, it is passed on to the `panel.groups` function, which must know what to do with it. By default, `panel.groups` is `panel.xyplot`, whose help page describes the admissible values. The functions `panel.superpose` and `panel.superpose.2` differ only in the default value of `distribute.type`, which controls the way the `type` argument is interpreted. If `distribute.type = FALSE`, then the interpretation is the same as for `panel.xyplot` for each of the unique groups. In other words, if `type` is a vector, all the individual components are honoured concurrently. If `distribute.type = TRUE`, `type` is replicated to be as long as the number of unique values in `groups`, and one component used for the points corresponding to the each different group. Even in this case, it is possible to request multiple types per group, specifying `type` as a list, each component being the desired `type` vector for the corresponding group. If `distribute.type = FALSE`, any occurrence of `"g"` in `type` causes a grid to be drawn, and all such occurrences are removed before `type` is passed on to `panel.groups`.
`grid` | Logical flag specifying whether a background reference grid should be drawn. See `panel.xyplot` for details.
`col` | A vector color specification. See Details.
`col.line` | A vector color specification. See Details.
`col.symbol` | A vector color specification. See Details.
`pch` | A vector plotting character specification. See Details.
`cex` | A vector size factor specification. See Details.
`fill` | A vector fill color specification. See Details.
`font, fontface, fontfamily` | A vector color specification. See Details.
`lty` | A vector color specification. See Details.
`lwd` | A vector color specification. See Details.
`alpha` | A vector alpha-transparency specification. See Details.
`...` | Extra arguments. Passed down to `panel.superpose` from `panel.superpose.2`, and to `panel.groups` from `panel.superpose`.
`distribute.type` | logical controlling interpretation of the `type` argument.

### Details

`panel.superpose` divides up the `x` (and optionally `y`) variable(s) by the unique values of `groups[subscripts]`, and plots each subset with different graphical parameters. The graphical parameters (`col.symbol`, `pch`, etc.) are usually supplied as suitable atomic vectors, but can also be lists. When `panel.groups` is called for the `i`-th level of `groups`, the corresponding element of each graphical parameter is passed to it. In the list form, the individual components can themselves be vectors.

The actual plot for each subgroup is created by the `panel.groups` function. With the default `panel.groups`, the `col` argument is overridden by `col.line` and `col.symbol` for lines and points respectively, which default to the `"superpose.line"` and `"superpose.symbol"` settings. However, `col` will still be supplied as an argument to `panel.groups` functions that make use of it, with a default of `"black"`. The defaults of other graphical parameters are also taken from the `"superpose.line"` and `"superpose.symbol"` settings as appropriate. The `alpha` parameter takes it default from the `"superpose.line"` setting.

`panel.superpose` and `panel.superpose.2` differ essentially in how `type` is interpreted by default. The default behaviour in `panel.superpose` is the opposite of that in S, which is the same as that of `panel.superpose.2`.

`panel.superpose.plain` is the same as `panel.superpose`, except that the default settings for the style arguments are the same for all groups and are taken from the default plot style. It is used in `xyplot.ts`.

### Author(s)

Deepayan Sarkar Deepayan.Sarkar@R-project.org (`panel.superpose.2` originally contributed by Neil Klepeis)

### See Also

Different functions when used as `panel.groups` gives different types of plots, for example `panel.xyplot`, `panel.dotplot` and `panel.average` (This can be used to produce interaction plots).

See `Lattice` for an overview of the package, and `xyplot` for common arguments (in particular, the discussion of the extended formula interface and the `groups` argument).

[Package lattice version 0.20-29 Index]