r.fuzzy.logic - GRASS GIS manual

NAME

r.fuzzy.logic - Performs logical operations on membership images created with r.fuzzy.set or different method. Use families for fuzzy logic.

KEYWORDS

raster, fuzzy logic

SYNOPSIS

r.fuzzy.logic

r.fuzzy.logic --help

r.fuzzy.logic xmap=name [ymap=name] output=name [operator=string] [family=string] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

--overwrite: Allow output files to overwrite existing files
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

xmap=name [required]: x operand (membership map)
ymap=name: y operand (membership map)
output=name [required]: Resulting map
operator=string: Fuzzy logic operation; Options: AND, OR, NOT, IMP; Default: AND
family=string: Fuzzy logic family; Options: Zadeh, product, drastic, Lukasiewicz, Fodor, Hamacher; Default: Zadeh

OPTIONS
OUTPUTS
SEE ALSO
REFERENCES
AUTHOR

OPTIONS

xmap

Name of input x membership operand. This map must be of type FCELL with range 0 :1 and may require null values. Otherwise program will print error message and stops.

ymap

Name of input y membership operand. This map must be of type FCELL with range 0 :1 and may require null values. Otherwise program will print error message and stops. This map is optional bit is required for all operation except NOT

operator

A fuzzy set operators are generalization of crisp operators. There is more than one possible generalization of every operator. There are three operations: fuzzy complements, fuzzy intersections, and fuzzy unions. Additional implication operator is also provided.

fuzzy intersection (AND) use T-norm of given family for calculation;
fuzzy union (OR) use T-conorm of given family for calculation;
fuzzy complement (NOT) fuzzy negation usually 1-x;
fuzzy implication (IMP) use residuum of given family if available;

family

T-norms, T-conorms and residuals are a generalization of the two-valued logical conjunction, disjunction and implication used by boolean logic, for fuzzy logics. Because there is more than one possible generalisation of logical operations, r.fuzzy.logic provides 6 most popular families for fuzzy operations:

Zadeh with minimum (Godel) t-norm and maximum T-conorm;
product with product T-norm and probabilistic sum as T-conorm;
drastic with drastic T-norm and drastic T-conorm;
Łukasiewicz with Łukasiewicz T-norm and bounded sum as a T-conorm;
Fodor with nilpotent minimum as T-norm and nilpotent maximum as T-conorm;
Hamacher (simplified) with Hamacher product as T-norm and Einstein sum as T-conorm;

There is no residuum for drastic and Hamacher families. For more details see Meyer D, Hornik K (2009); T-norms;

OUTPUTS

output: Map containing result of two-values operations. Map is always of type FCELL and contains values from 0 (no membership) to 1 (full membership). Values between 0 and 1 indicate partial membership