source: trunk/EventBenchConsole/src/de/ugoe/cs/eventbench/commands/CMDgenerateFixedLengthSequences.java @ 124

package de.ugoe.cs.eventbench.commands;

import java.security.InvalidParameterException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Random;
import java.util.Set;

import de.ugoe.cs.eventbench.data.Event;
import de.ugoe.cs.eventbench.data.GlobalDataContainer;
import de.ugoe.cs.eventbench.models.IStochasticProcess;
import de.ugoe.cs.util.console.Command;
import de.ugoe.cs.util.console.Console;

public class CMDgenerateFixedLengthSequences implements Command {

        @Override
        public void run(List<Object> parameters) {
                String modelname;
                String sequencesName;
                int minLength;
                int maxLength;
                boolean all = true;
                int numSequences = -1;
                try {
                        modelname = (String) parameters.get(0);
                        sequencesName = (String) parameters.get(1);
                        minLength = Integer.parseInt((String) parameters.get(2));
                        maxLength = Integer.parseInt((String) parameters.get(3));
                        if( parameters.size()>=5 ) {
                                all = Boolean.parseBoolean((String) parameters.get(4));
                        }
                        if( parameters.size()==6 ) {
                                numSequences = Integer.parseInt((String) parameters.get(5)); 
                        }
                }
                catch (Exception e) {
                        throw new InvalidParameterException();
                }
                
                IStochasticProcess model = null; 
                Object dataObject = GlobalDataContainer.getInstance().getData(modelname);
                if( dataObject==null ) {
                        Console.println("Model " + modelname + " not found in storage.");
                }
                else if( !(dataObject instanceof IStochasticProcess) ) {
                        Console.println("Object " + modelname + " not of type MarkovModel!");
                } else {
                        model = (IStochasticProcess) dataObject;
                        Collection<List<? extends Event<?>>> sequences = new LinkedHashSet<List<? extends Event<?>>>();
                        for( int length=minLength; length<maxLength; length++ ) {
                                sequences.addAll(model.generateValidSequences(length+2));
                        }
                        Console.traceln("" + sequences.size() + " possible");
                        if( !all && numSequences<sequences.size() ) {
                                List<Double> probabilities = new ArrayList<Double>(sequences.size());
                                double probSum = 0.0;
                                for( List<? extends Event<?>> sequence : sequences ) {
                                        double prob = model.getProbability(sequence);
                                        probabilities.add(prob);
                                        probSum += prob;
                                }
                                Set<Integer> drawnSequences = new HashSet<Integer>(numSequences);
                                Random r = new Random();
                                while( drawnSequences.size()<numSequences ) {
                                        double randVal = r.nextDouble()*probSum;
                                        double sum = 0.0d;
                                        int index = -1;
                                        while( sum<randVal ) {
                                                index++;
                                                double currentProb = probabilities.get(index);
                                                sum += currentProb;
                                        }
                                        if( !drawnSequences.contains(index) ) {
                                                drawnSequences.add(index);
                                                probSum -= probabilities.get(index);
                                                probabilities.set(index, 0.0d);
                                        }
                                }
                                Collection<List<? extends Event<?>>> retainedSequences = new LinkedList<List<? extends Event<?>>>();
                                int index = 0;
                                for( List<? extends Event<?>> sequence : sequences) {
                                        if( drawnSequences.contains(index) ) {
                                                retainedSequences.add(sequence);
                                        }
                                        index++;
                                }
                                sequences = retainedSequences;
                        }
                        if( GlobalDataContainer.getInstance().addData(sequencesName, sequences) ) {
                                Console.traceln("Old data \"" + sequencesName + "\" overwritten");
                        }
                        Console.println("" + sequences.size() + " sequences generated");
                }
        }

        @Override
        public void help() {
                Console.println("Usage: generateFixedLengthSequences <modelname> <sequencesName> <length> {<all>} {<numSequences>}");
        }

}