[ https://issues.apache.org/jira/browse/FLINK-3551?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15836701#comment-15836701 ]
ASF GitHub Bot commented on FLINK-3551: --------------------------------------- Github user fhueske commented on a diff in the pull request: https://github.com/apache/flink/pull/2761#discussion_r97657374 --- Diff: flink-examples/flink-examples-streaming/src/main/scala/org/apache/flink/streaming/scala/examples/ml/IncrementalLearningSkeleton.scala --- @@ -0,0 +1,205 @@ +/* + * 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.streaming.scala.examples.ml + +import java.util.concurrent.TimeUnit + +import org.apache.flink.api.java.utils.ParameterTool +import org.apache.flink.api.scala._ +import org.apache.flink.streaming.api.TimeCharacteristic +import org.apache.flink.streaming.api.functions.AssignerWithPunctuatedWatermarks +import org.apache.flink.streaming.api.functions.co.CoMapFunction +import org.apache.flink.streaming.api.functions.source.SourceFunction +import org.apache.flink.streaming.api.functions.source.SourceFunction.SourceContext +import org.apache.flink.streaming.api.scala.StreamExecutionEnvironment +import org.apache.flink.streaming.api.scala.function.AllWindowFunction +import org.apache.flink.streaming.api.watermark.Watermark +import org.apache.flink.streaming.api.windowing.time.Time +import org.apache.flink.streaming.api.windowing.windows.TimeWindow +import org.apache.flink.util.Collector + +/** + * Skeleton for incremental machine learning algorithm consisting of a + * pre-computed model, which gets updated for the new inputs and new input data + * for which the job provides predictions. + * + * <p> + * This may serve as a base of a number of algorithms, e.g. updating an + * incremental Alternating Least Squares model while also providing the + * predictions. + * + * <p> + * This example shows how to use: + * <ul> + * <li>Connected streams + * <li>CoFunctions + * <li>Tuple data types + * </ul> + */ +object IncrementalLearningSkeleton { + + // ************************************************************************* + // PROGRAM + // ************************************************************************* + + def main(args: Array[String]): Unit = { + // Checking input parameters + val params = ParameterTool.fromArgs(args) + + // set up the execution environment + val env = StreamExecutionEnvironment.getExecutionEnvironment + env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime) + + // build new model on every second of new data + val trainingData = env.addSource(new FiniteTrainingDataSource) + val newData = env.addSource(new FiniteNewDataSource) + + val model = trainingData + .assignTimestampsAndWatermarks(new LinearTimestamp) + .timeWindowAll(Time.of(5000, TimeUnit.MILLISECONDS)) + .apply(new PartialModelBuilder) + + // use partial model for newData + val prediction = newData.connect(model).map( + (_: Int) => 0, + (_: Array[Double]) => 1 + ) + + // emit result + if (params.has("output")) { + prediction.writeAsText(params.get("output")) + } else { + println("Printing result to stdout. Use --output to specify output path.") + prediction.print() + } + + // execute program + env.execute("Streaming Incremental Learning") + } + + // ************************************************************************* + // USER FUNCTIONS + // ************************************************************************* + + /** + * Feeds new data for newData. By default it is implemented as constantly + * emitting the Integer 1 in a loop. + */ + private class FiniteNewDataSource extends SourceFunction[Int] { + var counter: Int = 0 + + override def run(ctx: SourceContext[Int]) = { + Thread.sleep(15) --- End diff -- can be simplified to ``` Thread.sleep(15) (0 until 50).foreach{ _ => Thread.sleep(5) ctx.collect(1) } ``` > Sync Scala and Java Streaming Examples > -------------------------------------- > > Key: FLINK-3551 > URL: https://issues.apache.org/jira/browse/FLINK-3551 > Project: Flink > Issue Type: Sub-task > Components: Examples > Affects Versions: 1.0.0 > Reporter: Stephan Ewen > Assignee: Lim Chee Hau > > The Scala Examples lack behind the Java Examples -- This message was sent by Atlassian JIRA (v6.3.4#6332)