gghistogram {ggplot} | R Documentation

## Grob function: histogram

### Description

Draw a histogram

### Usage

    gghistogram(plot = .PLOT, aesthetics=list(), scale="prob", ..., data=NULL)

### Arguments

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

### Details

Aesthetic mappings that this grob function understands:

Conceptually, the histogram is one of the most complicated of the grob functions, becuase it takes a 1D data set and makes it two dimensional. This necessitates an extra step, the `pre_histogram` function which bins the data and returns the bins with their counts. This data is then used my `grob_histogram` to plot the points.

- `x`:x position (required)
- `weight`: observation weights

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:

- `breaks`:breaks argument passed to `hist`
- `scale`:scale argument passed to `hist`
- any other aesthetic setting passed on to `ggrect`

### Author(s)

Hadley Wickham <h.wickham@gmail.com>

### Examples

    m <- ggplot(movies, aesthetics=list(x=rating))
    gghistogram(m)
    gghistogram(m, breaks=100)
    qplot(length, data=movies, type="histogram")
    qplot(log(length), data=movies, type="histogram")
    m <- ggplot(movies, Action ~ Comedy, aesthetics=list(x=rating), margins=TRUE)
    gghistogram(m)
    gghistogram(m, scale="freq")
    gghistogram(m, colour="darkgreen", fill="white")
    qplot(rating, data=movies, type="histogram")
    qplot(rating, weight=votes, data=movies, type="histogram")
    qplot(rating, weight=votes, data=movies, type=c("histogram", "density"))

[Package ggplot version 0.4.2 Index]