| /** |
| * 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 com.datatorrent.contrib.r; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import org.rosuda.REngine.REngineException; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.datatorrent.lib.util.BaseNumberValueOperator; |
| |
| import com.datatorrent.api.Context; |
| import com.datatorrent.api.DefaultInputPort; |
| import com.datatorrent.api.DefaultOutputPort; |
| import com.datatorrent.api.Operator.Unifier; |
| |
| import com.datatorrent.netlet.util.DTThrowable; |
| |
| /** |
| * Emits at end of window, a maximum of all values sub-classed from Number in the incoming stream. <br> |
| * A vector is created in the process method. This vector is passed to the 'max' operator in R in the 'endWindow' |
| * function. <br> |
| * <b>StateFull :</b>Yes, max value is computed over application windows. <br> |
| * <b>Partitions :</b>Yes, operator is kin unifier operator. <br> |
| * <br> |
| * <b>Ports</b>:<br> |
| * <b>data</b>: expects V extends Number<br> |
| * <b>max</b>: emits V extends Number<br> |
| * <br> |
| * <br> |
| * |
| * @displayName R Max |
| * @category Scripting |
| * @tags script, r |
| * @since 2.1.0 |
| */ |
| |
| public class RMax<V extends Number> extends BaseNumberValueOperator<Number> implements Unifier<Number> |
| { |
| private List<Number> numList = new ArrayList<Number>(); |
| |
| private static Logger log = LoggerFactory.getLogger(RMax.class); |
| REngineConnectable connectable; |
| |
| public final transient DefaultInputPort<Number> data = new DefaultInputPort<Number>() { |
| /** |
| * Adds the tuple to the numList |
| */ |
| @Override |
| public void process(Number tuple) |
| { |
| RMax.this.process(tuple); |
| } |
| }; |
| |
| /** |
| * Adds the received tuple to the numList |
| */ |
| |
| @Override |
| public void process(Number tuple) |
| { |
| numList.add(tuple); |
| } |
| |
| public final transient DefaultOutputPort<Number> max = new DefaultOutputPort<Number>() { |
| @Override |
| public Unifier<Number> getUnifier() |
| { |
| return RMax.this; |
| } |
| }; |
| |
| /* |
| * Initialize the R engine |
| */ |
| @Override |
| public void setup(Context.OperatorContext context) |
| { |
| |
| super.setup(context); |
| try { |
| connectable = new REngineConnectable(); |
| connectable.connect(); |
| } catch (IOException ioe) { |
| log.error("Exception: ", ioe); |
| DTThrowable.rethrow(ioe); |
| } |
| |
| } |
| |
| /* |
| * Stop the R engine |
| */ |
| @Override |
| public void teardown() |
| { |
| |
| try { |
| connectable.disconnect(); |
| } catch (IOException ioe) { |
| log.error("Exception: ", ioe); |
| DTThrowable.rethrow(ioe); |
| } |
| |
| } |
| |
| /** |
| * Invokes the 'max' function from R to emit a maximum from the values received in the application window. Clears the |
| * numList at the end of the function. |
| **/ |
| |
| @Override |
| public void endWindow() |
| { |
| |
| if (numList.size() == 0) |
| return; |
| |
| double[] values = new double[numList.size()]; |
| for (int i = 0; i < numList.size(); i++) { |
| values[i] = numList.get(i).doubleValue(); |
| } |
| |
| try { |
| connectable.getRengine().assign("numList", values); |
| |
| } catch (REngineException e) { |
| log.error("Exception: ", e); |
| DTThrowable.rethrow(e); |
| } |
| |
| double rMax = 0; |
| try { |
| rMax = connectable.getRengine().parseAndEval("max(numList)").asDouble(); |
| connectable.getRengine().parseAndEval("rm(list = setdiff(ls(), lsf.str()))"); |
| } catch (Exception e) { |
| log.error("Exception: ", e); |
| DTThrowable.rethrow(e); |
| } |
| |
| log.debug(String.format("Max is : " + rMax)); |
| |
| max.emit(rMax); |
| numList.clear(); |
| |
| } |
| } |