R: Kernel Smoothed Intensity of Split Point Pattern

density.splitppp {spatstat} | R Documentation

## Kernel Smoothed Intensity of Split Point Pattern

### Description

Compute a kernel smoothed intensity function for each of the components of a split point pattern, or each of the point patterns in a list.

### Usage

      ## S3 method for class 'splitppp'
    density(x, ..., se=FALSE)

      ## S3 method for class 'ppplist'
    density(x, ..., se=FALSE)

### Arguments

`x` | Split point pattern (object of class `"splitppp"` created by `split.ppp`) to be smoothed. Alternatively a list of point patterns, of class `"ppplist"`.
`...` | Arguments passed to `density.ppp` to control the smoothing, pixel resolution, edge correction etc.
`se` | Logical value indicating whether to compute standard errors as well.

### Details

This is a method for the generic function `density`.

The argument `x` should be a list of point patterns, and should belong to one of the classes `"ppplist"` or `"splitppp"`.

Typically `x` is obtained by applying the function `split.ppp` to a point pattern `y` by calling `split(y)`. This splits the points of `y` into several sub-patterns.

A kernel estimate of the intensity function of each of the point patterns is computed using `density.ppp`.

The return value is usually a list, each of whose entries is a pixel image (object of class `"im"`). The return value also belongs to the class `"solist"` and can be plotted or printed.

If the argument `at="points"` is given, the result is a list of numeric vectors giving the intensity values at the data points.

If `se=TRUE`, the result is a list with two elements named `estimate` and `SE`, each of the format described above.

### Value

A list of pixel images (objects of class `"im"`) which can be plotted or printed; or a list of numeric vectors giving the values at specified points.

If `se=TRUE`, the result is a list with two elements named `estimate` and `SE`, each of the format described above.

### Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au

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

### See Also

`ppp.object`, `im.object`

### Examples

      Z <- density(split(amacrine), 0.05)
      plot(Z)

[Package spatstat version 1.54-0 Index]