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What Is Fuzzy Logic?

What Is Fuzzy Logic?

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Building <strong>Fuzzy</strong> Inference Systems Using Custom Functions<br />

variables, and nr is the number of rules. The output of the aggregation<br />

method is one fuzzy set for each output variable.<br />

The following is an example of a custom aggregation function:<br />

function aggfun = custom_agg(x)<br />

aggfun=(sum(x)/2).^0.5;<br />

Guidelines for Creating Custom Defuzzification Functions<br />

The custom defuzzification functions must be of the form y =<br />

custom_defuzz(xmf,ymf), where(xmf,ymf) is a finite set of membership<br />

function values. xmf is the vector of values in the membership function input<br />

range. ymf is the value of the membership function at xmf.<br />

The following is an example of a custom defuzzification function:<br />

function defuzzfun= custom_defuzz(xmf,ymf);<br />

total_area=sum(ymf);<br />

defuzzfun=sum(ymf*xmf)/total_area;<br />

Steps for Specifying Custom Inference Functions<br />

After you create and save a custom inference function, use the following steps<br />

to specify the function in the fuzzy inference process:<br />

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