| /* |
| * 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.model; |
| |
| import java.util.Objects; |
| |
| /** |
| * Provide a maximum entropy model with a uniform prior. |
| */ |
| public class UniformPrior implements Prior { |
| |
| private int numOutcomes; |
| private double r; |
| |
| public void logPrior(double[] dist, int[] context, float[] values) { |
| for (int oi = 0; oi < numOutcomes; oi++) { |
| dist[oi] = r; |
| } |
| } |
| |
| @Override |
| public void logPrior(double[] dist, Context[] context, float[] values) { |
| logPrior(dist, (int[]) null, values); |
| } |
| |
| public void logPrior(double[] dist, int[] context) { |
| logPrior(dist,context,null); |
| } |
| |
| public void setLabels(String[] outcomeLabels, String[] contextLabels) { |
| this.numOutcomes = outcomeLabels.length; |
| r = StrictMath.log(1.0 / numOutcomes); |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hash(numOutcomes, r); |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (obj == this) { |
| return true; |
| } |
| |
| if (obj instanceof UniformPrior) { |
| UniformPrior prior = (UniformPrior) obj; |
| |
| return numOutcomes == prior.numOutcomes && r == prior.r; |
| } |
| |
| return false; |
| } |
| } |