/**
* 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 org.apache.mahout.classifier.bayes;
import java.util.Collection;
import org.apache.mahout.classifier.ClassifierResult;
/**
* The algorithm interface for implementing variations of bayes Algorithm
*
*/
public interface Algorithm {
/**
* Initialize the data store and verifies the data in it.
*
* @param datastore
* @throws InvalidDatastoreException
*/
void initialize(Datastore datastore) throws InvalidDatastoreException;
/**
* Classify the document and return the Result
*
* @param document
* The document to classify
* @param datastore
* The data store(InMemory)
* @param defaultCategory
* The default category to assign Ties are broken by comparing the category
* @return A Collection of {@link org.apache.mahout.classifier.ClassifierResult}s.
* @throws InvalidDatastoreException
*/
ClassifierResult classifyDocument(String[] document,
Datastore datastore,
String defaultCategory) throws InvalidDatastoreException;
/**
* Classify the document and return the top {@code numResults}
*
* @param document
* The document to classify
* @param datastore
* The {@link Datastore} (InMemory)
* @param defaultCategory
* The default category to assign
* @param numResults
* The maximum number of results to return, ranked by score. Ties are broken by comparing the
* category
* @return A Collection of {@link ClassifierResult}s.
* @throws InvalidDatastoreException
*/
ClassifierResult[] classifyDocument(String[] document,
Datastore datastore,
String defaultCategory,
int numResults) throws InvalidDatastoreException;
/**
* Get the weighted probability of the feature.
*
* @param datastore
* The {@link Datastore} (InMemory)
* @param label
* The label of the feature
* @param feature
* The feature to calc. the prob. for
* @return The weighted probability
* @throws InvalidDatastoreException
*/
double featureWeight(Datastore datastore, String label, String feature) throws InvalidDatastoreException;
/**
* Calculate the document weight as the dot product of document vector and the corresponding weight vector
* of a particular class
*
* @param datastore
* The {@link Datastore} (InMemory)
* @param label
* The label to calculate the probability of
* @param document
* The document
* @return The probability
* @see Algorithm#featureWeight(Datastore, String, String)
*/
double documentWeight(Datastore datastore, String label, String[] document);
/**
* Returns the labels in the given Model
*
* @param datastore
* The {@link Datastore} (InMemory)
* @throws InvalidDatastoreException
* @return {@link Collection} of labels
*/
Collection<String> getLabels(Datastore datastore) throws InvalidDatastoreException;
}