geom_ribbon {ggplot2} | R Documentation

## Ribbons and area plots.

### Description

For each continuous x value, `geom_interval` displays a y interval. `geom_area` is a special case of `geom_ribbon`, where the minimum of the range is fixed to 0.

### Usage

    geom_ribbon(mapping = NULL, data = NULL, stat = "identity",
      position = "identity", ..., na.rm = FALSE, show.legend = NA,
      inherit.aes = TRUE)

    geom_area(mapping = NULL, data = NULL, stat = "identity",
      position = "stack", na.rm = FALSE, show.legend = NA,
      inherit.aes = TRUE, ...)

### Arguments

`mapping` | Set of aesthetic mappings created by `aes` or `aes_`. If specified and `inherit.aes = TRUE` (the default), it is combined with the default mapping at the top level of the plot. You must supply `mapping` if there is no plot mapping.

`data`

The data to be displayed in this layer. There are three options:

If `NULL`, the default, the data is inherited from the plot data as specified in the call to `ggplot`.

A `data.frame`, or other object, will override the plot data. All objects will be fortified to produce a data frame. See `fortify` for which variables will be created.

A `function` will be called with a single argument, the plot data. The return value must be a `data.frame.`, and will be used as the layer data.

`stat` | The statistical transformation to use on the data for this layer, as a string.
`position` | Position adjustment, either as a string, or the result of a call to a position adjustment function.
`...` | other arguments passed on to `layer`. These are often aesthetics, used to set an aesthetic to a fixed value, like `color = "red"` or `size = 3`. They may also be parameters to the paired geom/stat.
`na.rm` | If `FALSE` (the default), removes missing values with a warning. If `TRUE` silently removes missing values.
`show.legend` | logical. Should this layer be included in the legends? `NA`, the default, includes if any aesthetics are mapped. `FALSE` never includes, and `TRUE` always includes.
`inherit.aes` | If `FALSE`, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g. `borders`.

### Details

An area plot is the continuous analog of a stacked bar chart (see `geom_bar`), and can be used to show how composition of the whole varies over the range of x. Choosing the order in which different components is stacked is very important, as it becomes increasing hard to see the individual pattern as you move up the stack.

### Aesthetics

`geom_ribbon` understands the following aesthetics (required aesthetics are in bold):

- `x`

- `ymax`

- `ymin`

- `alpha`

- `colour`

- `fill`

- `linetype`

- `size`

### See Also

`geom_bar` for discrete intervals (bars), `geom_linerange` for discrete intervals (lines), `geom_polygon` for general polygons

### Examples

    # Generate data
    huron <- data.frame(year = 1875:1972, level = as.vector(LakeHuron))
    h <- ggplot(huron, aes(year))

    h + geom_ribbon(aes(ymin=0, ymax=level))
    h + geom_area(aes(y = level))

    # Add aesthetic mappings
    h +
      geom_ribbon(aes(ymin = level - 1, ymax = level + 1), fill = "grey70") +
      geom_line(aes(y = level))

[Package ggplot2 version 2.1.0 Index]