SAGA 9.12.3 | Tool Documentation

Shannon Index

Author(s) O.Conrad (c) 2019
Library IDgrid_analysis
Tool ID 22
Version 1.0
Menu Grid | Analysis | Diversity

Description

Grid based analysis of diversity with the Shannon Index. The index is calculated locally for each grid cell using the specified kernel (aka 'moving window'). It is assumed that the grid cell values represent a classification.

References

Pielou, E.C. (1969): An Introduction to Mathematical Ecology. John Wiley, New York.

Shannon, C. (1948): A mathematical theory of communication. Bell Syst. Tech. J. 27,379–423. doi:10.1002/j.1538-7305.1948.tb01338.x

Spellerberg, I.F. & Fedor, P.J. (2003): A tribute to Claude Shannon (1916–2001) and a plea for more rigorous use of species richness, species diversity and the 'Shannon-Wiener' Index. Global Ecology and Biogeography 12 (3), p. 177–179. doi:10.1046/j.1466-822X.2003.00015.x.

Parameters

 NameTypeIdentifierDescriptionConstraints
InputCategoriesgrid, inputCATEGORIES--
OutputNumber of Categoriesgrid, output, optionalCOUNTnumber of different categories (unique values) within search area-
Shannon Indexgrid, outputINDEX--
Evennessgrid, output, optionalEVENNESS--
OptionsGrid Systemgrid systemPARAMETERS_GRID_SYSTEM--
Kernel TypechoiceKERNEL_TYPEThe kernel's shape.Available Choices: [0] Square [1] Circle Default: 1
Radiusinteger numberKERNEL_RADIUScellsMinimum: 0 Default: 2

Command Line


Usage: saga_cmd grid_analysis 22 [-CATEGORIES ] [-COUNT ] [-INDEX ] [-EVENNESS ] [-KERNEL_TYPE ] [-KERNEL_RADIUS ]
  -CATEGORIES:      Categories
	grid, input
  -COUNT:           Number of Categories
	grid, output, optional
  -INDEX:           Shannon Index
	grid, output
  -EVENNESS:        Evenness
	grid, output, optional
  -KERNEL_TYPE:     Kernel Type
	choice
	Available Choices:
	[0] Square
	[1] Circle
	Default: 1
  -KERNEL_RADIUS:   Radius
	integer number
	Minimum: 0
	Default: 2