Fuzzy Inference System Modeling

Build fuzzy inference systems and fuzzy trees

Fuzzy inference is the process of formulating input/output mappings using fuzzy logic. Fuzzy Logic Toolbox™ software provides tools for creating:

Type-1 or interval type-2 Mamdani fuzzy inference systems
Type-1 or interval type-2 Sugeno fuzzy inference systems
Trees of interconnected fuzzy inference systems

For more information on fuzzy logic, seeWhat Is Fuzzy Logic?. For more information on fuzzy inference, seeFuzzy Inference Process.

Apps

Fuzzy Logic Designer

Design and test fuzzy inference systems

Functions

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Create Fuzzy Systems

Type-1 Systems

`mamfis`	Mamdani fuzzy inference system
`sugfis`	Sugeno fuzzy inference system
`genfis`	Generate fuzzy inference system object from data
`genfisOptions`	Option set for genfis command

Type-2 Systems

`mamfistype2`	Interval type-2 Mamdani fuzzy inference system
`sugfistype2`	Interval type-2 Sugeno fuzzy inference system

FIS Trees

fistree Network of connected fuzzy inference systems

FIS Conversion

`convertToSugeno`	Convert Mamdani fuzzy inference system into Sugeno fuzzy inference system
`convertToType1`	2型模糊推理系统转换成1型fuzzy inference system
`convertToType2`	Convert type-1 fuzzy inference system into type-2 fuzzy inference system
`convertToStruct`	Convert fuzzy inference system object into a structure
`convertfis`	Convert previous versions of fuzzy inference data in current format

Specify Input and Output Variables

`addInput`	Add input variable to fuzzy inference system
`addOutput`	Add output variable to fuzzy inference system
`removeInput`	Remove input variable from fuzzy inference system
`removeOutput`	Remove output variable from fuzzy inference system
`fisvar`	Fuzzy variable

Specify Membership Functions

`mfedit`	Open Membership Function Editor
`addMF`	Add membership function to fuzzy variable
`removeMF`	删除会员的乐趣ction from fuzzy variable
`fismf`	Fuzzy membership function
`fismftype2`	Interval type-2 fuzzy membership function

Specify Fuzzy Rules

`ruleedit`	Open Rule Editor
`ruleview`	Open Rule Viewer
`addRule`	Add rule to fuzzy inference system
`showrule`	Display fuzzy inference system rules
`fisrule`	Fuzzy rule
`update`	Update fuzzy rule using fuzzy inference system

Evaluate and Visualize Fuzzy Systems

`evalfis`	Evaluate fuzzy inference system
`evalfisOptions`	Option set for evalfis function
`plotfis`	Display fuzzy inference system
`plotmf`	Plot membership functions for input or output variable
`surfview`	Open Surface Viewer
`gensurf`	Generate fuzzy inference system output surface
`gensurfOptions`	Option set for gensurf function

Import and Export

`readfis`	Load fuzzy inference system from file
`writeFIS`	Save fuzzy inference system to file

Construct Custom Fuzzy Systems

`evalmf`	Evaluate fuzzy membership function
`gaussmf`	Gaussian membership function
`gbellmf`	Generalized bell-shaped membership function
`trimf`	Triangular membership function
`dsigmf`	Difference between two sigmoidal membership functions
`gauss2mf`	Gaussian combination membership function
`pimf`	Pi-shaped membership function
`psigmf`	Product of two sigmoidal membership functions
`sigmf`	Sigmoidal membership function
`smf`	S-shaped membership function
`trapmf`	Trapezoidal membership function
`zmf`	Z-shaped membership function
`defuzz`	Defuzzify membership function
`probor`	Probabilistic OR
`fuzarith`	Perform fuzzy arithmetic

Topics

Fuzzy Logic Basics

What Is Fuzzy Logic?

Fuzzy logic uses linguistic variables, defined as fuzzy sets, to approximate human reasoning.

Foundations of Fuzzy Logic

A fuzzy logic system is a collection of fuzzy if-then rules that perform logical operations on fuzzy sets.

Fuzzy Inference Process

Fuzzy inference maps an input space to an output space using a series of fuzzy if-then rules.

Fuzzy Inference Systems

Mamdani and Sugeno Fuzzy Inference Systems

You can implement either Mamdani or Sugeno fuzzy inference systems using Fuzzy Logic Toolbox software.

Type-2 Fuzzy Inference Systems

You can create and evaluate interval type-2 fuzzy inference systems with additional membership function uncertainty.

Fuzzy Trees

You can implement complex fuzzy inference systems as a collection of smaller interconnected fuzzy systems.

Build Fuzzy Inference Systems

Build Fuzzy Systems Using Fuzzy Logic Designer

Interactively construct a fuzzy inference system using the Fuzzy Logic Designer app.

Build Fuzzy Systems at the Command Line

Construct a fuzzy inference system at the MATLAB^®command line.

Build Fuzzy Systems Using Custom Functions

You can replace the built-in membership functions and fuzzy inference functions with your own custom functions.

Featured Examples

Fuzzy Logic Image Processing

You can use fuzzy logic for image processing tasks, such as edge detection.

Open Live Script

Fuzzy PID Control with Type-2 FIS

Create a type-2 fuzzy logic PID controller and compare its performance with a type-1 fuzzy PID controller and a conventional PID controller.