Extract.ppx {spatstat}R Documentation

Extract Subset of Multidimensional Point Pattern

Description

Extract a subset of a multidimensional point pattern.

Usage

  ## S3 method for class 'ppx'
x[i, drop=FALSE, ...]

Arguments

x

A multidimensional point pattern (object of class "ppx").

i

Subset index. A valid subset index in the usual R sense, indicating which points should be retained; or a spatial domain of class "boxx" or "box3".

drop

Logical value indicating whether to remove unused levels of the marks, if the marks are a factor.

...

Ignored.

Details

This function extracts a designated subset of a multidimensional point pattern.

The function [.ppx is a method for [ for the class "ppx". It extracts a designated subset of a point pattern. The argument i may be either

The argument drop determines whether to remove unused levels of a factor, if the point pattern is multitype (i.e. the marks are a factor) or if the marks are a data frame or hyperframe in which some of the columns are factors.

Use the function unmark to remove marks from a marked point pattern.

Value

A multidimensional point pattern (of class "ppx").

Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au, Rolf Turner r.turner@auckland.ac.nz and Ege Rubak rubak@math.aau.dk

See Also

ppx

Examples

   df <- data.frame(x=runif(4),y=runif(4),z=runif(4))
   X <- ppx(data=df, coord.type=c("s","s","t"))
   X[-2]

[Package spatstat version 1.64-1 Index]