# get_boltzmann: Boltzmann entropy of a landscape gradient In r-spatialecology/belg: Boltzmann Entropy of a Landscape Gradient

## Description

Calculates the Boltzmann entropy of a landscape gradient

## Usage

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19``` ```get_boltzmann(x, base = "log10", relative = FALSE, method = "hierarchy") ## Default S3 method: get_boltzmann(x, base = "log10", relative = FALSE, method = "hierarchy") ## S3 method for class 'matrix' get_boltzmann(x, base = "log10", relative = FALSE, method = "hierarchy") ## S3 method for class 'array' get_boltzmann(x, base = "log10", relative = FALSE, method = "hierarchy") ## S3 method for class 'RasterLayer' get_boltzmann(x, base = "log10", relative = FALSE, method = "hierarchy") ## S3 method for class 'RasterStack' get_boltzmann(x, base = "log10", relative = FALSE, method = "hierarchy") ## S3 method for class 'RasterBrick' get_boltzmann(x, base = "log10", relative = FALSE, method = "hierarchy") ```

## Arguments

 `x` RasterLayer, RasterStack, RasterBrick, matrix, or array `base` A logarithm base ("log", "log2" or "log10") `relative` TRUE/FALSE `method` A method used. Either "hierarchy" (default) for the hierarchy-based method (Gao et al., 2017) or "aggregation" for the aggregation-based method (Gao et al., 2019)

## Details

The method for computing the Boltzmann entropy of a landscape gradient works on integer values that are either positive or equals to zero. This function automatically rounds values to the nearest integer value (rounding halfway cases away from zero) and negative values are shifted to positive values.

a numeric vector

## References

Gao, Peichao, Hong Zhang, and Zhilin Li. "A hierarchy-based solution to calculate the configurational entropy of landscape gradients." Landscape Ecology 32.6 (2017): 1133-1146.

Gao, Peichao, Hong Zhang, and Zhilin Li. "An efficient analytical method for computing the Boltzmann entropy of a landscape gradient." Transactions in GIS (2018).

Gao, Peichao and Zhilin Li. "Aggregation-based method for computing absolute Boltzmann entropy of landscape gradient with full thermodynamic consistency" Landscape Ecology (2019)

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13``` ```new_c = c(56, 86, 98, 50, 45, 56, 96, 25, 15, 55, 85, 69, 12, 52, 25, 56, 32, 25, 68, 98, 58, 66, 56, 58) lg = matrix(new_c, nrow = 3, ncol = 8, byrow = TRUE) get_boltzmann(lg, relative = FALSE, base = "log10") get_boltzmann(lg, relative = TRUE, base = "log2") get_boltzmann(lg, relative = TRUE, base = "log") get_boltzmann(lg, relative = FALSE, method = "aggregation") get_boltzmann(lg, relative = TRUE, method = "aggregation") ```

r-spatialecology/belg documentation built on Dec. 9, 2019, 2:32 a.m.