R: Extract or Replace Subset of a Layered Object

Extract.layered {spatstat} | R Documentation

## Extract or Replace Subset of a Layered Object

### Description

Extract or replace some or all of the layers of a layered object, or extract a spatial subset of each layer.

### Usage

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

      ## S3 replacement method for class 'layered'
    x[i] <- value

      ## S3 replacement method for class 'layered'
    x[[i]] <- value

### Arguments

`x` | A layered object (class `"layered"`).
`i` | Subset index for the list of layers. A logical vector, integer vector or character vector specifying which layers are to be extracted or replaced.
`j` | Subset index to be applied to the data in each layer. Typically a spatial window (class `"owin"`).
`drop` | Logical. If `i` specifies only a single layer and `drop=TRUE`, then the contents of this layer will be returned.
`...` | Additional arguments, passed to other subset methods if the subset index is a window.
`value` | List of objects which shall replace the designated subset, or an object which shall replace the designated element.

### Details

A layered object represents data that should be plotted in successive layers, for example, a background and a foreground. See `layered`.

The function `[.layered` extracts a designated subset of a layered object. It is a method for `[` for the class `"layered"`.

The functions `[<-.layered` and `[[<-.layered` replace a designated subset or designated entry of the object by new values. They are methods for `[<-` and `[[<-` for the `"layered"` class.

The index `i` specifies which layers will be retained. It should be a valid subset index for the list of layers.

The index `j` will be applied to each layer. It is typically a spatial window (class `"owin"`) so that each of the layers will be restricted to the same spatial region. Alternatively `j` may be any subset index which is permissible for the `"["` method for each of the layers.

### Value

Usually an object of class `"layered"`.

### 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

`layered`

### Examples

     D <- distmap(cells)
     L <- layered(D, cells,
                  plotargs=list(list(ribbon=FALSE), list(pch=16)))

     L[-2]
     L[, square(0.5)]

     L[[3]] <- japanesepines
     L

[Package spatstat version 1.54-0 Index]