Reasoner.java :  » App » imhotep » piramide » multimodal » preprocessor » Android Open Source

/*
 * Copyright (C) 2010 PIRAmIDE-SP3 authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 * This software consists of contributions made by many individuals, 
 * listed below:
 *
 * Author: Aitor Almeida <aitor.almeida@deusto.es>
 *         Pablo Ordua <pablo.orduna@deusto.es>
 *
 */

package piramide.multimodal.preprocessor;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

import net.sourceforge.jFuzzyLogic.FIS;
import net.sourceforge.jFuzzyLogic.rule.Variable;

public class Reasoner {
  
  private FIS fuzzyEngine;
  final static private String FILE_NAME = "fcl/tipper.fcl";
  final static String NO_TERM = "NO_TERM";
  final static String FUNCTION_BLOCK_NAME = "variableInferenceRules";
  
  public Reasoner()
  {
    this.loadRules(Reasoner.FILE_NAME);
  }
  
  public Map<String, Object> expandVariables (Map<String, Object> initialVariableValues)
  {
    Map<String, Object> finalVariableValues = initialVariableValues;
    if( this.fuzzyEngine != null ) {
      setInputs(initialVariableValues);
      this.fuzzyEngine.evaluate();      
      
      final Map<String, String> inferredVariableValues = this.getAllOutputTerms(Reasoner.FUNCTION_BLOCK_NAME);
      for(Iterator<String> keys = inferredVariableValues.keySet().iterator(); keys.hasNext();){
        String key = keys.next();
        //If something has been inferred
        if (!inferredVariableValues.get(key).equals(Reasoner.NO_TERM))
          finalVariableValues.put(key, inferredVariableValues.get(key));
      }
    }
    return finalVariableValues;
  }
  
  public void loadRules(String fileName){    
      this.fuzzyEngine = FIS.load(fileName,true);
      if( this.fuzzyEngine == null ) { 
          System.out.println("Invalid file");
      }    
  }
  
  public void setInputs(Map<String, Object> inputVars){       
      Set<String> keys = inputVars.keySet();
      for (String varName : keys) {
        try {
          Double varValue = Double.valueOf(inputVars.get(varName).toString());
          this.fuzzyEngine.setVariable(varName, varValue);        
      } catch (NumberFormatException e) {
        System.out.println(varName + "is not a number");
      }      
    }
  }
  
  public String getMostProbableValue(Variable variable)
  {
    String bestTerm = "";
    Double bestValue = 0.0;
  
    //search for the most probable term
    //TODO add some kind of minimal tresshold to the membership value
    for (Iterator<String> terms = variable.iteratorLinguisticTermNames(); terms.hasNext();) {
      String term = terms.next();
      if (variable.getMembership(term) >= bestValue){
        bestTerm = term;
        bestValue = variable.getMembership(term);
      }
    }
    //If the best value is not positive nothing has been inferred for this variable
    if (bestValue == 0.0)
      return Reasoner.NO_TERM;
    else
      return bestTerm;
  }
  
  public Map<String, String> getAllOutputTerms(String functionBlockName)
  {
    HashMap<String, String> res = new HashMap<String,String>();
    HashMap <String, Variable> variables = this.fuzzyEngine.getFunctionBlock(functionBlockName).getVariables();
    for(Iterator<Variable> varValues = variables.values().iterator();varValues.hasNext();){
      Variable variable = varValues.next();
      //we are only interested in output variables
      if (variable.isOutputVarable()){
        res.put(variable.getName(), this.getMostProbableValue(variable));
      }
    }
    return res;
  }

  
  //For debug purposes only
  public void showChart (){
    this.fuzzyEngine.chart();    
  }
  
  

}