R: Test whether Object is Multitype

is.multitype {spatstat.geom} | R Documentation

## Test whether Object is Multitype

### Description

Generic function to test whether a given object (usually a point pattern or something related to a point pattern) has “marks” attached to the points which classify the points into several types.

### Usage

      is.multitype(X, ...)

### Arguments

`X` | Object to be inspected
`...` | Other arguments.

### Details

“Marks” are observations attached to each point of a point pattern. For example the `longleaf` dataset contains the locations of trees, each tree being marked by its diameter; the `amacrine` dataset gives the locations of cells of two types (on/off) and the type of cell may be regarded as a mark attached to the location of the cell. Other objects related to point patterns, such as point process models, may involve marked points.

This function tests whether the object `X` contains or involves marked points, and that the marks are a factor.

For example, the `amacrine` dataset is multitype (there are two types of cells, on and off), but the `longleaf` dataset is not multitype (the marks are real numbers).

This function is generic; methods are provided for point patterns (objects of class `"ppp"`) and point process models (objects of class `"ppm"`).

### Value

Logical value, equal to `TRUE` if `X` is multitype.

### Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au

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

### See Also

`is.multitype.ppp`, `is.multitype.ppm`

[Package spatstat.geom version 2.2-0 Index]