R: Spatially Sampled Function

ssf {spatstat.core} | R Documentation

## Spatially Sampled Function

### Description

Create an object that represents a spatial function which has been evaluated or sampled at an irregular set of points.

### Usage

      ssf(loc, val)

### Arguments

`loc` | The spatial locations at which the function has been evaluated. A point pattern (object of class `"ppp"`).
`val` | The function values at these locations. A numeric vector with one entry for each point of `loc`, or a data frame with one row for each point of `loc`.

### Details

An object of class `"ssf"` represents a real-valued or vector-valued function that has been evaluated or sampled at an irregular set of points. An example would be a spatial covariate that has only been measured at certain locations.

An object of this class also inherits the class `"ppp"`, and is essentially the same as a marked point pattern, except for the class membership which enables it to be handled in a different way.

There are methods for `plot`, `print` etc; see `plot.ssf` and `methods.ssf`.

Use `unmark` to extract only the point locations, and `marks.ssf` to extract only the function values.

### Value

Object of class `"ssf"`.

### Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au

### See Also

`plot.ssf`, `methods.ssf`, `Smooth.ssf`, `with.ssf`, `[.ssf`.

### Examples

      ssf(cells, nndist(cells, k=1:3))

[Package spatstat.core version 2.3-0 Index]