使用 kmeans 对数据进行聚类时出错

Posted 2023-03-12

【中文标题】使用 kmeans 对数据进行聚类时出错

【英文标题】：Error while clustering data with kmeans

【发布时间】：2011-12-08 18:42:19

【问题描述】：

我正在尝试对此处显示的输入数据执行 k 均值算法的聚类： https://cwiki.apache.org/MAHOUT/clustering-of-synthetic-control-data.html 然而，当地图减少工作即将发生时，我得到了错误

11/10/16 21:05:57 INFO mapred.JobClient: Task Id : attempt_201110161920_0008_m_000000_0,     Status : FAILED
Error: java.lang.ClassNotFoundException: org.apache.mahout.math.Vector
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:247)
at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:762)
at org.apache.hadoop.io.WritableName.getClass(WritableName.java:71)
at org.apache.hadoop.io.SequenceFile$Reader.getValueClass(SequenceFile.java:1613)
at org.apache.hadoop.io.SequenceFile$Reader.init(SequenceFile.java:1555)
at org.apache.hadoop.io.SequenceFile$Reader.<init>(SequenceFile.java:1428)
at org.apache.hadoop.io.SequenceFile$Reader.<init>(SequenceFile.java:1417)
at org.apache.hadoop.io.SequenceFile$Reader.<init>(SequenceFile.java:1412)
at org.apache.hadoop.mapreduce.lib.input.SequenceFileRecordReader.initialize(SequenceFileRecordReader.java:50)
at org.apache.hadoop.mapred.MapTask$NewTrackingRecordReader.initialize(MapTask.java:418)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:620)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:305)
at org.apache.hadoop.mapred.Child.main(Child.java:170)

11/10/16 21:06:03 INFO mapred.JobClient: Task Id : attempt_201110161920_0008_m_000000_1, Status : FAILED
Error: java.lang.ClassNotFoundException: org.apache.mahout.math.Vector
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:247)
at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:762)
at org.apache.hadoop.io.WritableName.getClass(WritableName.java:71)
at org.apache.hadoop.io.SequenceFile$Reader.getValueClass(SequenceFile.java:1613)
at org.apache.hadoop.io.SequenceFile$Reader.init(SequenceFile.java:1555)
at org.apache.hadoop.io.SequenceFile$Reader.<init>(SequenceFile.java:1428)
at org.apache.hadoop.io.SequenceFile$Reader.<init>(SequenceFile.java:1417)
at org.apache.hadoop.io.SequenceFile$Reader.<init>(SequenceFile.java:1412)
at   org.apache.hadoop.mapreduce.lib.input.SequenceFileRecordReader.initialize(SequenceFileRecordReader.java:50)
at    org.apache.hadoop.mapred.MapTask$NewTrackingRecordReader.initialize(MapTask.java:418)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:620)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:305)
at org.apache.hadoop.mapred.Child.main(Child.java:170)

11/10/16 21:06:09 INFO mapred.JobClient: Task Id : attempt_201110161920_0008_m_000000_2,     Status : FAILED
    Error: java.lang.ClassNotFoundException: org.apache.mahout.math.Vector
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:247)
at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:762)
at org.apache.hadoop.io.WritableName.getClass(WritableName.java:71)
at org.apache.hadoop.io.SequenceFile$Reader.getValueClass(SequenceFile.java:1613)
at org.apache.hadoop.io.SequenceFile$Reader.init(SequenceFile.java:1555)
at org.apache.hadoop.io.SequenceFile$Reader.<init>(SequenceFile.java:1428)
at org.apache.hadoop.io.SequenceFile$Reader.<init>(SequenceFile.java:1417)
at org.apache.hadoop.io.SequenceFile$Reader.<init>(SequenceFile.java:1412)
at org.apache.hadoop.mapreduce.lib.input.SequenceFileRecordReader.initialize(SequenceFileRecordReader.java:50)
at org.apache.hadoop.mapred.MapTask$NewTrackingRecordReader.initialize(MapTask.java:418)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:620)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:305)
at org.apache.hadoop.mapred.Child.main(Child.java:170)

11/10/16 21:06:18 INFO mapred.JobClient: Job complete: job_201110161920_0008
11/10/16 21:06:18 INFO mapred.JobClient: Counters: 3
11/10/16 21:06:18 INFO mapred.JobClient:   Job Counters 
11/10/16 21:06:18 INFO mapred.JobClient:     Launched map tasks=4
11/10/16 21:06:18 INFO mapred.JobClient:     Data-local map tasks=4
11/10/16 21:06:18 INFO mapred.JobClient:     Failed map tasks=1
Exception in thread "main" java.lang.InterruptedException: K-Means Iteration failed processing output/clusters-0/part-randomSeed
at org.apache.mahout.clustering.kmeans.KMeansDriver.runIteration(KMeansDriver.java:363)
at org.apache.mahout.clustering.kmeans.KMeansDriver.buildClustersMR(KMeansDriver.java:310)
at org.apache.mahout.clustering.kmeans.KMeansDriver.buildClusters(KMeansDriver.java:237)
at org.apache.mahout.clustering.kmeans.KMeansDriver.run(KMeansDriver.java:152)
at org.apache.mahout.clustering.syntheticcontrol.kmeans.Job.run(Job.java:149)
at org.apache.mahout.clustering.syntheticcontrol.kmeans.Job.main(Job.java:60)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:68)
at org.apache.hadoop.util.ProgramDriver.driver(ProgramDriver.java:139)
at org.apache.mahout.driver.MahoutDriver.main(MahoutDriver.java:187)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.hadoop.util.RunJar.main(RunJar.java:156)

有人可以告诉我如何纠正这个问题。这真的意味着很多。 感谢您的宝贵时间。

【参考方案1】：

这意味着您没有向 Hadoop 提供运行作业所需的所有类。您发送给它的 JAR 文件必须打包所有依赖项，包括来自其核心和数学模块的所有 Mahout 类。幸运的是，Mahout 为您做到了这一点。查看它在构建时创建的“作业”文件，该文件出现在 target/ 中。

【讨论】：

我是看examples/target目录还是新生成的target目录？

他们说 Mahout 的 mahout-examples-$MAHOUT_VERSION.job 执行实际的集群任务，因此需要创建它。你能告诉我如何创建这个吗？我真的很感谢你的帮助。我想我在这一步出错了。

【参考方案2】：

您缺少 org.apache.mahout.math 包：

Error: java.lang.ClassNotFoundException: org.apache.mahout.math.Vector