histbackback {Hmisc} | R Documentation |

## Back to Back Histograms

### Description

Takes two vectors or a list with `x`

and `y`

components, and produces
back to back histograms of the two datasets.

### Usage

```
histbackback(x, y, brks=NULL, xlab=NULL, axes=TRUE, probability=FALSE,
xlim=NULL, ylab='', ...)
```

### Arguments

`x` , `y` |
either two vectors or a list given as |

`brks` |
vector of the desired breakpoints for the histograms. |

`xlab` |
a vector of two character strings naming the two datasets. |

`axes` |
logical flag stating whether or not to label the axes. |

`probability` |
logical flag: if |

`xlim` |
x-axis limits. First value must be negative, as the left histogram is
placed at negative x-values. Second value must be positive, for the
right histogram. To make the limits symmetric, use e.g. |

`ylab` |
label for y-axis. Default is no label. |

`...` |
additional graphics parameters may be given. |

### Value

a list is returned invisibly with the following components:

`left` |
the counts for the dataset plotted on the left. |

`right` |
the counts for the dataset plotted on the right. |

`breaks` |
the breakpoints used. |

### Side Effects

a plot is produced on the current graphics device.

### Author(s)

Pat Burns

Salomon Smith Barney

London

pburns@dorado.sbi.com

### See Also

### Examples

```
options(digits=3)
set.seed(1)
histbackback(rnorm(20), rnorm(30))
fool <- list(x=rnorm(40), y=rnorm(40))
histbackback(fool)
age <- rnorm(1000,50,10)
sex <- sample(c('female','male'),1000,TRUE)
histbackback(split(age, sex))
agef <- age[sex=='female']; agem <- age[sex=='male']
histbackback(list(Female=agef,Male=agem), probability=TRUE, xlim=c(-.06,.06))
```

*Hmisc*version 5.1-3 Index]