# hist.im

##### Histogram of Pixel Values in an Image

Computes and displays a histogram of the pixel values in a pixel image.
The `hist`

method for class `"im"`

.

##### Usage

```
## S3 method for class 'im':
hist(x, \dots, probability=FALSE)
```

##### Arguments

- x
- A pixel image (object of class
`"im"`

). - ...
- Arguments passed to
`hist.default`

or`barplot`

. - probability
- Logical. If
`TRUE`

, the histogram will be normalised to give probabilities or probability densities.

##### Details

This function computes and (by default) displays a histogram
of the pixel values in the image `x`

.

An object of class `"im"`

describes a pixel image. See `im.object`

)
for details of this class.

The function `hist.im`

is a method for the generic
function `hist`

for the class `"im"`

.
Any arguments in `...`

are passed to `hist.default`

(for numeric valued images) or `barplot`

(for factor or
logical images).
For example, such arguments control the axes, and may be used to
suppress the plotting.

##### Value

- For numeric-valued images, an object of class
`"histogram"`

as returned by`hist.default`

. This object can be plotted. For factor-valued or logical images, an object of class`"barplotdata"`

, which can be plotted. This is a list with components called`counts`

(contingency table of counts of the numbers of pixels taking each possible value),`probs`

(corresponding relative frequencies) and`mids`

(graphical $x$-coordinates of the midpoints of the bars in the barplot).

##### See Also

`spatialcdf`

for the cumulative distribution function
of an image.
`hist`

,
`hist.default`

,
`barplot`

.

For information about pixel images see
`im.object`

,
`summary.im`

.

##### Examples

```
X <- as.im(function(x,y) {x^2}, unit.square())
hist(X)
hist(cut(X,3))
```

*Documentation reproduced from package spatstat, version 1.42-2, License: GPL (>= 2)*