/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
package opennlp.maxent;
import java.io.File;
import java.io.FileReader;
import opennlp.maxent.io.GISModelWriter;
import opennlp.maxent.io.SuffixSensitiveGISModelWriter;
import opennlp.model.AbstractModel;
import opennlp.model.AbstractModelWriter;
import opennlp.model.EventStream;
import opennlp.model.OnePassDataIndexer;
import opennlp.model.OnePassRealValueDataIndexer;
import opennlp.perceptron.PerceptronTrainer;
import opennlp.perceptron.SuffixSensitivePerceptronModelWriter;
/**
* Main class which calls the GIS procedure after building the EventStream from
* the data.
*/
public class ModelTrainer {
// some parameters if you want to play around with the smoothing option
// for model training. This can improve model accuracy, though training
// will potentially take longer and use more memory. Model size will also
// be larger. Initial testing indicates improvements for models built on
// small data sets and few outcomes, but performance degradation for those
// with large data sets and lots of outcomes.
public static boolean USE_SMOOTHING = false;
public static double SMOOTHING_OBSERVATION = 0.1;
private static void usage() {
System.err.println("java ModelTrainer [-real] dataFile modelFile");
System.exit(1);
}
/**
* Main method. Call as follows:
* <p>
* java ModelTrainer dataFile modelFile
*/
public static void main(String[] args) {
int ai = 0;
boolean real = false;
String type = "maxent";
int maxit = 100;
int cutoff = 1;
double sigma = 1.0;
if (args.length == 0) {
usage();
}
while (args[ai].startsWith("-")) {
if (args[ai].equals("-real")) {
real = true;
} else if (args[ai].equals("-perceptron")) {
type = "perceptron";
} else if (args[ai].equals("-maxit")) {
maxit = Integer.parseInt(args[++ai]);
} else if (args[ai].equals("-cutoff")) {
cutoff = Integer.parseInt(args[++ai]);
} else if (args[ai].equals("-sigma")) {
sigma = Double.parseDouble(args[++ai]);
} else {
System.err.println("Unknown option: " + args[ai]);
usage();
}
ai++;
}
String dataFileName = new String(args[ai++]);
String modelFileName = new String(args[ai]);
try {
FileReader datafr = new FileReader(new File(dataFileName));
EventStream es;
if (!real) {
es = new BasicEventStream(new PlainTextByLineDataStream(datafr), ",");
} else {
es = new RealBasicEventStream(new PlainTextByLineDataStream(datafr));
}
File outputFile = new File(modelFileName);
AbstractModelWriter writer;
AbstractModel model;
if (type.equals("maxent")) {
GIS.SMOOTHING_OBSERVATION = SMOOTHING_OBSERVATION;
if (!real) {
model = GIS.trainModel(es, maxit, cutoff, sigma);
} else {
model = GIS.trainModel(maxit,
new OnePassRealValueDataIndexer(es, cutoff),
USE_SMOOTHING);
}
writer = new SuffixSensitiveGISModelWriter(model, outputFile);
} else if (type.equals("perceptron")) {
//System.err.println("Perceptron training");
model = new PerceptronTrainer().trainModel(maxit, new OnePassDataIndexer(es, cutoff), cutoff);
writer = new SuffixSensitivePerceptronModelWriter(model, outputFile);
} else {
throw new RuntimeException("Unknown model type: " + type);
}
writer.persist();
} catch (Exception e) {
System.out.print("Unable to create model due to exception: ");
System.out.println(e);
e.printStackTrace();
}
}
}