R: First or Last Part of a Spatial Pattern

headtail {spatstat} | R Documentation

## First or Last Part of a Spatial Pattern

### Description

Returns the first few elements (`head`) or the last few elements (`tail`) of a spatial pattern.

### Usage

      ## S3 method for class 'ppp'
    head(x, n = 6L, ...)

      ## S3 method for class 'ppx'
    head(x, n = 6L, ...)

      ## S3 method for class 'psp'
    head(x, n = 6L, ...)

      ## S3 method for class 'tess'
    head(x, n = 6L, ...)

      ## S3 method for class 'ppp'
    tail(x, n = 6L, ...)

      ## S3 method for class 'ppx'
    tail(x, n = 6L, ...)

      ## S3 method for class 'psp'
    tail(x, n = 6L, ...)

      ## S3 method for class 'tess'
    tail(x, n = 6L, ...)

### Arguments

`x` | A spatial pattern of geometrical figures, such as a spatial pattern of points (an object of class `"ppp"`, `"pp3"`, `"ppx"` or `"lpp"`) or a spatial pattern of line segments (an object of class `"psp"`) or a tessellation (object of class `"tess"`).
`n` | Integer. The number of elements of the pattern that should be extracted.
`...` | Ignored.

### Details

These are methods for the generic functions `head` and `tail`. They extract the first or last `n` elements from `x` and return them as an object of the same kind as `x`.

To inspect the spatial coordinates themselves, use `View(x)` or `head(as.data.frame(x))`.

### Value

An object of the same class as `x`.

### 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

`View`, `edit`.

Conversion to data frame: `as.data.frame.ppp`, `as.data.frame.ppx`, `as.data.frame.psp`

### Examples

      head(cells)
      tail(as.psp(spiders), 10)
      head(dirichlet(cells), 4)

[Package spatstat version 1.63-3 Index]