DiversityDom {StrucDiv}

Spatial Structural Diversity Metrics

Description

The functions entropyDom , entropyNormDom, contrastDom, dissimilarityDom and homogeneityDom are the spatial structural diversity metrics used in the default configurations of strucDivDom. For programming reasons, these metrics have different name endings than the metrics used in the functions strucDiv and strucDivNest, but they have the same mathematical formulation. Hence, entropyDom is specified by the same equation as entropy, and so forth. Structural diversity entropy is entropyDom with different delta parameters. Shannon entropy is employed, when delta = 0. The metric entropyDom has a scale-dependent maximum. Scale, here, refers to the extent of the domain. The metric entropyNormDom is Shannon entropy normalized over maximum entropy. The metric entropyNormDom ranges between 0 and 1. Additionally, the value gradient is considered with delta = 1 and delta = 2. The values of structural diversity entropy with delta = 1 or delta = 2 are not restricted and depend on the values of the input raster. The metric dissimilarityDom employs delta = 1, contrastDom employs delta = 2. The values of dissimilarityDom and contrastDom are not restricted and depend on the values of the input raster. The metric homogeneityDom quantifies the closeness of empirical probabilities to the diagonal and ranges between 0 and 1.

Usage

homogeneityDom(rank, delta, PMat, xVal, nrp)

dissimilarityDom(rank, delta, PMat, xVal, nrp)

contrastDom(rank, delta, PMat, xVal, nrp)

entropyDom(rank, delta, PMat, xVal, nrp)

entropyNormDom(rank, delta, PMat, xVal, nrp)

Arguments

rank

logical. Should values be replaced with ranks in the co-occurrence matrix (GLCM)? Defaults to FALSE.

delta

numeric, takes 3 options: 0, 1, or 2. The parameter delta is the difference weight parameter, it defines how the differences between pixel values within a pixel pair should be weighted. If rank = TRUE, delta defines how the differences between ranks should be weighted. The default value is 0 (no weight). Set delta = 1 for absolute weights, or delta = 2 for square weights. The delta parameter can only be set when the metric entropyDom is used. The metric dissimilarityDom automatically employs delta = 1, and contrastDom employs delta = 2.

PMat

the GLCM that is returned by an internal function to the strucDivDom function.

xVal

the unique values in the raster layer. calculated internally.

nrp

the normalizing constant calculated internally based on the raster dimensions.

Details

These functions are used internally and are called as an argument to the strucDivDom.