/*
* 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.tools.ml.maxent.io;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import opennlp.tools.ml.model.AbstractModel;
import opennlp.tools.ml.model.AbstractModelWriter;
import opennlp.tools.ml.model.ComparablePredicate;
import opennlp.tools.ml.model.Context;
import opennlp.tools.ml.model.IndexHashTable;
/**
* Abstract parent class for GISModel writers. It provides the persist method
* which takes care of the structure of a stored document, and requires an
* extending class to define precisely how the data should be stored.
*/
public abstract class GISModelWriter extends AbstractModelWriter {
protected Context[] PARAMS;
protected String[] OUTCOME_LABELS;
protected int CORRECTION_CONSTANT;
protected double CORRECTION_PARAM;
protected String[] PRED_LABELS;
public GISModelWriter(AbstractModel model) {
Object[] data = model.getDataStructures();
PARAMS = (Context[]) data[0];
IndexHashTable<String> pmap = (IndexHashTable<String>) data[1];
OUTCOME_LABELS = (String[]) data[2];
CORRECTION_CONSTANT = (Integer) data[3];
CORRECTION_PARAM = (Double) data[4];
PRED_LABELS = new String[pmap.size()];
pmap.toArray(PRED_LABELS);
}
/**
* Writes the model to disk, using the <code>writeX()</code> methods provided
* by extending classes.
*
* <p>
* If you wish to create a GISModelWriter which uses a different structure, it
* will be necessary to override the persist method in addition to
* implementing the <code>writeX()</code> methods.
*/
public void persist() throws IOException {
// the type of model (GIS)
writeUTF("GIS");
// the value of the correction constant
writeInt(CORRECTION_CONSTANT);
// the value of the correction constant
writeDouble(CORRECTION_PARAM);
// the mapping from outcomes to their integer indexes
writeInt(OUTCOME_LABELS.length);
for (int i = 0; i < OUTCOME_LABELS.length; i++)
writeUTF(OUTCOME_LABELS[i]);
// the mapping from predicates to the outcomes they contributed to.
// The sorting is done so that we actually can write this out more
// compactly than as the entire list.
ComparablePredicate[] sorted = sortValues();
List<List<ComparablePredicate>> compressed = compressOutcomes(sorted);
writeInt(compressed.size());
for (int i = 0; i < compressed.size(); i++) {
List a = compressed.get(i);
writeUTF(a.size() + a.get(0).toString());
}
// the mapping from predicate names to their integer indexes
writeInt(PARAMS.length);
for (int i = 0; i < sorted.length; i++)
writeUTF(sorted[i].name);
// write out the parameters
for (int i = 0; i < sorted.length; i++)
for (int j = 0; j < sorted[i].params.length; j++)
writeDouble(sorted[i].params[j]);
close();
}
protected ComparablePredicate[] sortValues() {
ComparablePredicate[] sortPreds = new ComparablePredicate[PARAMS.length];
int numParams = 0;
for (int pid = 0; pid < PARAMS.length; pid++) {
int[] predkeys = PARAMS[pid].getOutcomes();
// Arrays.sort(predkeys);
int numActive = predkeys.length;
int[] activeOutcomes = predkeys;
double[] activeParams = PARAMS[pid].getParameters();
numParams += numActive;
/*
* double[] activeParams = new double[numActive];
*
* int id = 0; for (int i=0; i < predkeys.length; i++) { int oid =
* predkeys[i]; activeOutcomes[id] = oid; activeParams[id] =
* PARAMS[pid].getParams(oid); id++; }
*/
sortPreds[pid] = new ComparablePredicate(PRED_LABELS[pid],
activeOutcomes, activeParams);
}
Arrays.sort(sortPreds);
return sortPreds;
}
protected List<List<ComparablePredicate>> compressOutcomes(ComparablePredicate[] sorted) {
ComparablePredicate cp = sorted[0];
List<List<ComparablePredicate>> outcomePatterns = new ArrayList<List<ComparablePredicate>>();
List<ComparablePredicate> newGroup = new ArrayList<ComparablePredicate>();
for (int i = 0; i < sorted.length; i++) {
if (cp.compareTo(sorted[i]) == 0) {
newGroup.add(sorted[i]);
} else {
cp = sorted[i];
outcomePatterns.add(newGroup);
newGroup = new ArrayList<ComparablePredicate>();
newGroup.add(sorted[i]);
}
}
outcomePatterns.add(newGroup);
return outcomePatterns;
}
}