ggerrorbar {ggplot} | R Documentation

## Grob function: error bars

### Description

Add error bars to a plot

### Usage

    ggerrorbar(plot = .PLOT, aesthetics = list(), ..., data = NULL)

### Arguments

`plot` | the plot object to modify
`aesthetics` | named list of aesthetic mappings, see details for more information
`...` | other options, see details for more information
`data` | data source, if not specified the plot default will be used

### Details

The error bar grob adds error bars to a plot. Thanks to Timm Danker for supplying some initial code and the motivation to include it in ggplot.

Aesthetic mappings that this grob function understands:

- `x`:x position (required)
- `y`:y position (required)
- `plus`:length of error bar in positive direction (required)
- `minus`:length of error bar in negative direction (defaults to -plus)
- `colour`:line colour (see `sccolour)`
- `size`:size of the line, in mm (see `scsize)`

These can be specified in the plot defaults (see `ggplot`) or in the `aesthetics` argument. If you want to modify the position of the points or any axis options, you will need to add a position scale to the plot. These functions start with `ps`, eg. `pscontinuous` or `pscategorical`

Other options:

- `avoid`: how should overplotting be dealt with? "none" (default) = do nothing, "stack" = stack bars on top of one another, "dodge" = dodge bars from side to side

### Author(s)

Hadley Wickham <h.wickham@gmail.com>

### See Also

`ggbar`

### Examples

    df <- data.frame(x = factor(c(1, 1, 2, 2)), y = c(1, 5, 3, 4), g = c(1, 2, 1, 2), bar = c(0.1,
    0.3, 0.3, 0.2))
    df2<-df[c(1,3),];df2

    p <- ggbar(ggplot(data=df, aes=list(fill=g, y=y, x=x)))
    ggerrorbar(p, aes=list(plus=bar))
    qplot(x,y,df,types=list("bar","errorbar"), avoid="dodge",aes=list(fill=g,plus=bar))
    qplot(x,y,df,types=list("bar","errorbar"), avoid="dodge",aes=list(fill=g,plus=bar, minus=-2*bar))
    qplot(x,y,df2,types=list("point","errorbar"), aes=list(plus=bar), width=0.1)
    qplot(x,y,df2,types=list("bar","line","point","errorbar"), aes=list(fill=g,plus=bar,barcolour=g))
    qplot(x,y,df2,types=list("jitter","errorbar"), aes=list(plus=bar))
    qplot(x,y,df,types=list("point","line","errorbar"), aes=list(plus=bar,id=g), width=0.1)

[Package ggplot version 0.4.2 Index]