Java tutorial
/** * 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.cloudera.knittingboar.records; import java.io.File; import org.apache.commons.io.FileUtils; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapred.FileInputFormat; import org.apache.hadoop.mapred.InputSplit; import org.apache.hadoop.mapred.JobConf; import org.apache.hadoop.mapred.TextInputFormat; import org.apache.mahout.classifier.sgd.L1; import org.apache.mahout.classifier.sgd.OnlineLogisticRegression; import org.apache.mahout.math.DenseVector; import org.apache.mahout.math.RandomAccessSparseVector; import org.apache.mahout.math.Vector; import org.junit.After; import org.junit.Before; import org.junit.Test; import com.cloudera.knittingboar.io.InputRecordsSplit; import com.cloudera.knittingboar.utils.TestingUtils; import com.google.common.io.Files; public class TestTwentyNewsgroupsCustomRecordParseOLRRun { private static final Log LOG = LogFactory.getLog(TestTwentyNewsgroupsCustomRecordParseOLRRun.class.getName()); private static final int FEATURES = 10000; private JobConf defaultConf; private FileSystem localFs; private File baseDir; private Path workDir; private String inputFileName; @Before public void setup() throws Exception { defaultConf = new JobConf(); defaultConf.set("fs.defaultFS", "file:///"); localFs = FileSystem.getLocal(defaultConf); inputFileName = "kboar-shard-0.txt"; baseDir = Files.createTempDir(); File inputFile = new File(baseDir, inputFileName); TestingUtils.copyDecompressed(inputFileName + ".gz", inputFile); workDir = new Path(baseDir.getAbsolutePath()); } @After public void teardown() throws Exception { FileUtils.deleteQuietly(baseDir); } @Test public void testRecordFactoryOnDatasetShard() throws Exception { // TODO a test with assertions is not a test // p.270 ----- metrics to track lucene's parsing mechanics, progress, // performance of OLR ------------ double averageLL = 0.0; double averageCorrect = 0.0; int k = 0; double step = 0.0; int[] bumps = new int[] { 1, 2, 5 }; TwentyNewsgroupsRecordFactory rec_factory = new TwentyNewsgroupsRecordFactory("\t"); // rec_factory.setClassSplitString("\t"); JobConf job = new JobConf(defaultConf); long block_size = localFs.getDefaultBlockSize(workDir); LOG.info("default block size: " + (block_size / 1024 / 1024) + "MB"); // matches the OLR setup on p.269 --------------- // stepOffset, decay, and alpha --- describe how the learning rate decreases // lambda: amount of regularization // learningRate: amount of initial learning rate @SuppressWarnings("resource") OnlineLogisticRegression learningAlgorithm = new OnlineLogisticRegression(20, FEATURES, new L1()).alpha(1) .stepOffset(1000).decayExponent(0.9).lambda(3.0e-5).learningRate(20); FileInputFormat.setInputPaths(job, workDir); // try splitting the file in a variety of sizes TextInputFormat format = new TextInputFormat(); format.configure(job); Text value = new Text(); int numSplits = 1; InputSplit[] splits = format.getSplits(job, numSplits); LOG.info("requested " + numSplits + " splits, splitting: got = " + splits.length); LOG.info("---- debug splits --------- "); rec_factory.Debug(); int total_read = 0; for (int x = 0; x < splits.length; x++) { LOG.info("> Split [" + x + "]: " + splits[x].getLength()); int count = 0; InputRecordsSplit custom_reader = new InputRecordsSplit(job, splits[x]); while (custom_reader.next(value)) { Vector v = new RandomAccessSparseVector(TwentyNewsgroupsRecordFactory.FEATURES); int actual = rec_factory.processLine(value.toString(), v); String ng = rec_factory.GetNewsgroupNameByID(actual); // calc stats --------- double mu = Math.min(k + 1, 200); double ll = learningAlgorithm.logLikelihood(actual, v); averageLL = averageLL + (ll - averageLL) / mu; Vector p = new DenseVector(20); learningAlgorithm.classifyFull(p, v); int estimated = p.maxValueIndex(); int correct = (estimated == actual ? 1 : 0); averageCorrect = averageCorrect + (correct - averageCorrect) / mu; learningAlgorithm.train(actual, v); k++; int bump = bumps[(int) Math.floor(step) % bumps.length]; int scale = (int) Math.pow(10, Math.floor(step / bumps.length)); if (k % (bump * scale) == 0) { step += 0.25; LOG.info(String.format("%10d %10.3f %10.3f %10.2f %s %s", k, ll, averageLL, averageCorrect * 100, ng, rec_factory.GetNewsgroupNameByID(estimated))); } learningAlgorithm.close(); count++; } LOG.info("read: " + count + " records for split " + x); total_read += count; } // for each split LOG.info("total read across all splits: " + total_read); rec_factory.Debug(); } }