R: Areas of Morphological Erosions

eroded.areas {spatstat} | R Documentation

## Areas of Morphological Erosions

### Description

Computes the areas of successive morphological erosions of a window.

### Usage

     eroded.areas(w, r, subset=NULL)

### Arguments

`w` | A window.
`r` | Numeric vector of radii at which erosions will be performed.
`subset` | Optional window inside which the areas should be computed.

### Details

This function computes the areas of the erosions of the window `w` by each of the radii `r[i]`.

The morphological erosion of a set W by a distance r > 0 is the subset consisting of all points x in W such that the distance from x to the boundary of W is greater than or equal to r. In other words it is the result of trimming a margin of width r off the set W.

The argument `r` should be a vector of positive numbers. The argument `w` should be a window (an object of class `"owin"`, see `owin.object` for details) or can be given in any format acceptable to `as.owin()`.

Unless `w` is a rectangle, the computation is performed using a pixel raster approximation.

To compute the eroded window itself, use `erosion`.

### Value

Numeric vector, of the same length as `r`, giving the areas of the successive erosions.

### Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au

and Rolf Turner r.turner@auckland.ac.nz

### See Also

`owin`, `as.owin`, `erosion`

### Examples

      w <- owin(c(0,1),c(0,1))
      a <- eroded.areas(w, seq(0.01,0.49,by=0.01))

[Package spatstat version 1.54-0 Index]