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ASF GitHub Bot commented on FLINK-2044: --------------------------------------- Github user gallenvara commented on a diff in the pull request: https://github.com/apache/flink/pull/1956#discussion_r62868637 --- Diff: flink-libraries/flink-gelly/src/main/java/org/apache/flink/graph/library/HITSAlgorithm.java --- @@ -0,0 +1,183 @@ +/* + * 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.flink.graph.library; + +import org.apache.flink.api.common.aggregators.DoubleSumAggregator; +import org.apache.flink.api.common.functions.MapFunction; +import org.apache.flink.api.java.DataSet; + +import org.apache.flink.api.java.tuple.Tuple2; +import org.apache.flink.graph.Edge; +import org.apache.flink.graph.EdgeDirection; +import org.apache.flink.graph.Graph; +import org.apache.flink.graph.GraphAlgorithm; +import org.apache.flink.graph.Vertex; +import org.apache.flink.graph.spargel.MessageIterator; +import org.apache.flink.graph.spargel.MessagingFunction; +import org.apache.flink.graph.spargel.ScatterGatherConfiguration; +import org.apache.flink.graph.spargel.VertexUpdateFunction; +import org.apache.flink.graph.utils.NullValueEdgeMapper; +import org.apache.flink.types.DoubleValue; +import org.apache.flink.types.NullValue; +import org.apache.flink.util.Preconditions; + +/** + * This is an implementation of HITS algorithm, using a scatter-gather iteration. + * The user can define the maximum number of iterations. HITS algorithm is determined by two parameters, + * hubs and authorities. A good hub represents a page that points to many other pages, and a good authority + * represented a page that is linked by many different hubs. + * Each vertex has a value of Tuple2 type, the first field is hub score and the second field is authority score. + * The implementation assumes that the two score are the same in each vertex at the beginning. + * <p> + * + * @see <a href="https://en.wikipedia.org/wiki/HITS_algorithm">HITS Algorithm</a> + */ +public class HITSAlgorithm<K, VV, EV> implements GraphAlgorithm<K, VV, EV, DataSet<Vertex<K, Tuple2<Double, Double>>>> { + + private int maxIterations; + + /** + * Creates an instance of HITS algorithm. + * + * @param maxIterations the maximum number of iterations + */ + public HITSAlgorithm(int maxIterations) { + Preconditions.checkArgument(maxIterations > 0, "The number of maximum iteration should be greater than 0."); + this.maxIterations = maxIterations * 2 + 1; + } + + @Override + public DataSet<Vertex<K, Tuple2<Double, Double>>> run(Graph<K, VV, EV> netGraph) throws Exception { + + ScatterGatherConfiguration parameter = new ScatterGatherConfiguration(); + parameter.setDirection(EdgeDirection.ALL); + parameter.registerAggregator("sumVertexValue", new DoubleSumAggregator()); + + return netGraph + .mapVertices(new VertexInitMapper<K, VV>()) + .mapEdges(new NullValueEdgeMapper<K, EV>()) --- End diff -- Yes, and i will modify the code. > Implementation of Gelly HITS Algorithm > -------------------------------------- > > Key: FLINK-2044 > URL: https://issues.apache.org/jira/browse/FLINK-2044 > Project: Flink > Issue Type: New Feature > Components: Gelly > Reporter: Ahamd Javid > Assignee: GaoLun > Priority: Minor > > Implementation of Hits Algorithm in Gelly API using Java. the feature branch > can be found here: (https://github.com/JavidMayar/flink/commits/HITS) -- This message was sent by Atlassian JIRA (v6.3.4#6332)