What Is Fuzzy Logic?

psigmf
Purpose
Syntax
Description
Built-in membership function composed of product of two sigmoidally
shaped membership functions
y = psigmf(x,[a1 c1 a2 c2])
The sigmoid curve plotted for the vector x depends on two parameters
a and c as given by
1
f( x; a, c)
=
+
− −
1
e ax ( c )
psigmf is simply the product of two such curves plotted for the values
of the vector x
f 1
(x; a 1
, c 1
)×f 2
(x; a 2
, c 2
)
The parameters are listed in the order [a 1
c 1
a 2
c 2
].
Examples
x=0:0.1:10;
y=psigmf(x,[2 3 -5 8]);
plot(x,y)
xlabel('psigmf, P=[2 3 -5 8]')
1
0.75
0.5
0.25
0
0 2 4 6 8 10
psigmf, P = [2 3 −5 8]
See Also
dsigmf, gaussmf, gauss2mf, gbellmf, evalmf, mf2mf, pimf, sigmf, smf,
trapmf, trimf, zmf
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