What Is Fuzzy Logic?

sffis
Purpose
Syntax
Description
Fuzzy inference S-function for Simulink software
output = sffis(t,x,u,flag,fismat)
In most cases, the Fuzzy Logic Controller block generates a custom
block diagram for your FIS. The Fuzzy Wizard, however, cannot handle
FIS with custom membership functions or with AND, OR, IMP, and
AGG functions outside of the following list:
• orMethod:max
• andMethod: min,prod
• impMethod: min,prod
• aggMethod: max
In these cases, the Fuzzy Logic Controller block uses the S-function
sffis to simulate the FIS. For more discussion of this topic, see
“Building Your Own Fuzzy Simulink Models” on page 2-93.
The MEX-file sffis is used by Simulink to undertake the calculation
normally performed by evalfis. It has been optimized to work in
the Simulink environment. sffis builds a data structure in memory
during the initialization phase of a Simulink simulation, which it then
continues to use until the simulation is complete.
The arguments t, x, andflag are standard Simulink S-function
arguments (see Writing S-Functions in the Simulink documentation).
The argument u is the input to the MATLAB workspace FIS structure,
fismat. If, for example, there are two inputs to fismat, thenu is a
two-element vector.
See Also
evalfis, fuzblock
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