contagpixelgrid

adjacency

Function for calculating the classic pixel-adjacency contagion landscape metric from a binary map (O'Neill, 1988).

Functions for estimating the gliding box lacunarity (GBL),
covariance, and pair-correlation of a random closed set (RACS) in 2D
from a binary coverage map (e.g. presence-absence land cover maps).
Contains a number of newly-developed covariance-based estimators of
GBL (Hingee et al., 2019) <doi:10.1007/s13253-019-00351-9> and
balanced estimators, proposed by Picka (2000)
<http://www.jstor.org/stable/1428408>, for covariance, centred
covariance, and pair-correlation. Also contains methods for
estimating contagion-like properties of RACS and simulating 2D Boolean
models. Binary coverage maps are usually represented as raster images
with pixel values of TRUE, FALSE or NA, with NA representing
unobserved pixels. A demo for extracting such a binary map from a
geospatial data format is provided. Binary maps may also be
represented using polygonal sets as the foreground, however for most
computations such maps are converted into raster images. The package
is based on research conducted during the author's PhD studies.

Kassel Hingee

lacunaritycovariance

Gliding Box Lacunarity and Other Metrics for 2D Random Closed
Sets

contagpixelgrid function

<dl><dt>xi</dt>
<dd>A raster binary map (as an <code>im</code> object) or as a foreground set (as an <code>owin</code> object).
In the latter case the observation window, <code>obswin</code>, must be supplied.
See <code>lacunaritycovariance-package</code> for details.
If <code>xi</code> is an <code>owin</code> object it must be of <code>mask</code> type.</dd>
<dt>obswin</dt>
<dd>If <code>xi</code> is an <code>owin</code> object then <code>obswin</code> is an
<code>owin</code> object that specifies the observation window.</dd>
<dt>normalise</dt>
<dd>If <code>TRUE</code> will divide result by \(2 ln(2)\) and add 1 to make contagion between 0 and 1 for all binary maps.</dd></dl>

Arguments

<ul>
<li><code>contagpixelgrid()</code>: Pixel-adjacency contagion landscape metric of a binary map.</li>
<li><code>adjacency()</code>: Calculates the adjacency matrix used in the pixel contagion</li>
</ul>

Functions

Will fail if map is either all foreground or all background.

Warning

Pixel Adjacency Contagion — contagpixelgrid

<dl>

<dt>xi</dt>
<dd>A raster binary map (as an <code>im</code> object) or as a foreground set (as an <code>owin</code> object).
In the latter case the observation window, <code>obswin</code>, must be supplied.
See <code>lacunaritycovariance-package</code> for details.
If <code>xi</code> is an <code>owin</code> object it must be of <code>mask</code> type.</dd>


<dt>obswin</dt>
<dd>If <code>xi</code> is an <code>owin</code> object then <code>obswin</code> is an
<code>owin</code> object that specifies the observation window.</dd>


<dt>normalise</dt>
<dd>If <code>TRUE</code> will divide result by \(2 ln(2)\) and add 1 to make contagion between 0 and 1 for all binary maps.</dd>

</dl>

	Second pixel in `xi`	Second pixel not in `xi`
First pixel in `xi`	-	-
First pixel not in `xi`	-	-

contagpixelgrid: Pixel Adjacency Contagion

Description

Usage

Value

Arguments

Functions

Warning

Details

References

Examples