R: Plot quantile lines

bxplot {beeswarm} | R Documentation

## Plot quantile lines

### Description

Plot lines indicating the specified quantiles for each group. This function is intended as a simplified interpretation of `boxplot`, which can be combined with a `beeswarm` (or `stripchart`) plot.

### Usage

    bxplot(x, ...)

    ## S3 method for class 'formula'
    bxplot(formula, data = NULL, ..., subset, na.action = NULL)

    ## Default S3 method:
    bxplot(x, probs = c(0.25, 0.5, 0.75),
        vertical = TRUE, horizontal = !vertical, add = FALSE,
        col = par("col"), lty = par("lty"), lwd = NULL,
        at = NULL, width = 0.75, ...)

### Arguments

`formula` | A formula, such as `y ~ grp`, where `y` is a numeric vector of data values to be split into groups according to the grouping variable `grp` (usually a factor).
`data` | A data.frame (or list) from which the variables in `formula` should be taken.
`subset` | An optional vector specifying a subset of observations to be used.
`na.action` | A function which indicates what should happen when the data contain `NA`s. The default is to quietly ignore missing values in either the response or the group.
`x` | A numeric vector, or a data frame or list of numeric vectors, each of which is considered as a group.
`probs` | A numeric vector of probabilities with values in [0,1]
`vertical, horizontal` | Orientation of the plot. `horizontal` takes precedence if both are specified.
`add` | Add to an existing plot?
`col, lty` | Color and line type for each probability.
`lwd` | Line width for each probability (see below).
`at` | Numeric vector giving the locations where the swarms should be drawn; defaults to `1:n` where n is the number of groups.
`width` | Width of the lines.
`...` | Further arguments passed to `boxplot`.

### Details

This function is intended as a minimalistic interpration of `boxplot`; however, the quantiles plotted by `bxplot` are not necessarily the same as the hinges plotted by a `boxplot`.

Notice that specifying a vector of graphical parameters such as `lwd` or `col` will refer to each of `probs`, not to each group in the data (as one might expect by analogy with `boxplot`).

If `lwd` is `NULL`, and if the `probs` includes 0.5, `lwd` will be set to 3 times `par("lwd")` for probs=0.5, and `par("lwd")` for the others. (Thus something resembling the median line and hinges of a boxplot is produced by default.)

### Value

None.

### Examples

      ## bxplot on bottom
      beeswarm(len ~ dose, data = ToothGrowth)
      bxplot(len ~ dose, data = ToothGrowth, add = TRUE)

      ## bxplot on top
      bxplot(decrease ~ treatment, data = OrchardSprays, probs = 0.5, col = 2)
      beeswarm(decrease ~ treatment, data = OrchardSprays, add = TRUE)

      ## Show deciles
      data(breast)
      bxplot(time_survival ~ event_survival, data = breast,
        probs = seq(0, 1, by = 0.1), col = rainbow(10))
      beeswarm(time_survival ~ event_survival, data = breast,
        pch = 21, bg = "gray75", add = TRUE)

[Package beeswarm version 0.4.0 Index]