jFuzzyLogic/html/html_old/example_parametric_optimization_content.html

<center><h3> Optimization example </h3></center>

Java code to optimize fuzzy sets' parameters and fuzzy rule's weights<p>

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<pre>
//---
// Load FIS (Fuzzy Inference System)
//---
FIS fis = FIS.load("fcl/qualify.fcl");
RuleBlock ruleBlock = fis.getFunctionBlock().getRuleBlock();

//---
// Create a list of parameter to optimize
//---
ArrayList<Parameter> parameterList = new ArrayList<Parameter>();

// Add variables. 
// Note: Fuzzy sets' parameters for these 
// variables will be optimized
Parameter.parameterListAddVariable(parameterList
                                    , fis.getVariable("scoring"));
Parameter.parameterListAddVariable(parameterList
                                    , fis.getVariable("credLimMul"));

// Add every rule's weight
for( Rule rule = ruleBlock ) 
    Parameter.parameterListAddRule(parameterList, rule);

//---
// Create an error function to be 
// optimzed (i.e. minimized)
//---
ErrorFunctionQualify errorFunction = new ErrorFunctionQualify();

//---
// Optimize (using 'Delta jump optimization')
//---
OptimizationDeltaJump optimizationDeltaJump = 
        new OptimizationDeltaJump(ruleBlock
                , errorFunction, parameterList);

// Number optimization of iterations
optimizationDeltaJump.setMaxIterations(20);

optimizationDeltaJump.optimize(true);
</pre>
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<p>
The error funcion (in this particular case, ErrorFunctionQualify) can be just any error function, the structure for the code should be like this:

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<pre>
public class ErrorFunctionQualify extends ErrorFunction {
    public double evaluate(RuleBlock ruleBlock) {
        double error;
        // Caculate your desired error here...
        return error;
    }
}    
</pre>
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