找网站公司做网站用了织梦可以吗,wordpress防止并发数,企业建站用什么主机,国内新闻最新消息2022需求分析
需要对数据集进行预处理#xff0c;选择合适的特征进行聚类分析#xff0c;确定聚类的数量和初始中心点#xff0c;调用Mahout提供的K-Means算法进行聚类计算#xff0c;评估聚类结果的准确性和稳定性。同时#xff0c;需要对Mahout的使用和参数调优进行深入学习…需求分析
需要对数据集进行预处理选择合适的特征进行聚类分析确定聚类的数量和初始中心点调用Mahout提供的K-Means算法进行聚类计算评估聚类结果的准确性和稳定性。同时需要对Mahout的使用和参数调优进行深入学习和实践以保证聚类结果的有效性和可靠性。
系统实现 1.对实验整体的理解 本次实验我们的目的是理解聚类的原理并且掌握常见聚类的算法以及掌握使用Mahout实现K-Means聚类分析算法的过程。 2.实验整体流程分析
创建项目导入开发依赖包编写工具类编写聚类分析的代码将聚类结果输出评估聚类的效果 3.准备工作
使用IDEA创建一个Maven项目mahout_kmeans_demo 修改pom.xml文件导入开发MapReduce所需的Jar包 dependenciesdependencygroupIdorg.apache.hadoop/groupIdartifactIdhadoop-hdfs/artifactIdversion2.6.0/version/dependencydependencygroupIdorg.apache.hadoop/groupIdartifactIdhadoop-client/artifactIdversion2.6.0/version/dependencydependencygroupIdorg.apache.hadoop/groupIdartifactIdhadoop-common/artifactIdversion2.6.0/version/dependencydependencygroupIdorg.apache.hadoop/groupIdartifactIdhadoop-mapreduce-client-common/artifactIdversion2.6.0/version/dependencydependencygroupIdorg.apache.hadoop/groupIdartifactIdhadoop-mapreduce-client-core/artifactIdversion2.6.0/version/dependencydependencygroupIdorg.apache.mahout/groupIdartifactIdmahout-mr/artifactIdversion0.13.0/version/dependencydependencygroupIdorg.apache.mahout/groupIdartifactIdmahout-math/artifactIdversion0.13.0/version/dependencydependencygroupIdorg.apache.mahout/groupIdartifactIdmahout-hdfs/artifactIdversion0.13.0/version/dependencydependencygroupIdorg.apache.mahout/groupIdartifactIdmahout-integration/artifactIdversion0.13.0/version/dependencydependencygroupIdorg.apache.mahout/groupIdartifactIdmahout-examples/artifactIdversion0.13.0/version/dependency
/dependencies
下载相关依赖包 等待pom.xml文件不再出现错误即可 准备实验数据并下载 启动Hadoop集群。
终端输入start-all.sh 可以使用jps命令查看集群启动情况。 4.执行聚类过程
编写工具类HdfsUtil对HDFS的基本操作进行封装
package com;import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.*;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.mapred.JobConf;import java.io.IOException;
import java.net.URI;public class HdfsUtil {private static final String HDFS hdfs://master:9000/;private String hdfsPath;private Configuration conf;public HdfsUtil(Configuration conf) {this(HDFS, conf);}public HdfsUtil(String hdfs, Configuration conf) {this.hdfsPath hdfs;this.conf conf;}public static JobConf config() {JobConf conf new JobConf(HdfsUtil.class);conf.setJobName(HdfsDAO);return conf;}public void mkdirs(String folder) throws IOException {Path path new Path(folder);FileSystem fs FileSystem.get(URI.create(hdfsPath), conf);if (!fs.exists(path)) {fs.mkdirs(path);System.out.println(Create: folder);}fs.close();}public void rmr(String folder) throws IOException {Path path new Path(folder);FileSystem fs FileSystem.get(URI.create(hdfsPath), conf);fs.deleteOnExit(path);System.out.println(Delete: folder);fs.close();}public void ls(String folder) throws IOException {Path path new Path(folder);FileSystem fs FileSystem.get(URI.create(hdfsPath), conf);FileStatus[] list fs.listStatus(path);System.out.println(ls: folder);System.out.println();for (FileStatus f : list) {System.out.printf(name: %s, folder: %s, size: %d\n, f.getPath(), f.isDir(), f.getLen());}System.out.println();fs.close();}public void createFile(String file, String content) throws IOException {FileSystem fs FileSystem.get(URI.create(hdfsPath), conf);byte[] buff content.getBytes();FSDataOutputStream os null;try {os fs.create(new Path(file));os.write(buff, 0, buff.length);System.out.println(Create: file);} finally {if (os ! null)os.close();}fs.close();}public void copyFile(String local, String remote) throws IOException {FileSystem fs FileSystem.get(URI.create(hdfsPath), conf);fs.copyFromLocalFile(new Path(local), new Path(remote));System.out.println(copy from: local to remote);fs.close();}public void download(String remote, String local) throws IOException {Path path new Path(remote);FileSystem fs FileSystem.get(URI.create(hdfsPath), conf);fs.copyToLocalFile(path, new Path(local));System.out.println(download: from remote to local);fs.close();}public void cat(String remoteFile) throws IOException {Path path new Path(remoteFile);FileSystem fs FileSystem.get(URI.create(hdfsPath), conf);FSDataInputStream fsdis null;System.out.println(cat: remoteFile);try {fsdis fs.open(path);IOUtils.copyBytes(fsdis, System.out, 4096, false);} finally {IOUtils.closeStream(fsdis);fs.close();}}
}
编写KMeansMahout类执行聚类过程
package com;import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.mahout.clustering.Cluster;
import org.apache.mahout.clustering.canopy.CanopyDriver;
import org.apache.mahout.clustering.conversion.InputDriver;
import org.apache.mahout.clustering.kmeans.KMeansDriver;
import org.apache.mahout.common.HadoopUtil;
import org.apache.mahout.common.distance.EuclideanDistanceMeasure;
import org.apache.mahout.utils.clustering.ClusterDumper;public class KMeansMahout {private static final String HDFS hdfs://master:9000;public static void main(String[] args) throws Exception {String localFile /home/data/iris.dat;// mahout输出至HDFS的目录String outputPath HDFS /user/hdfs/kmeans/output;// mahout的输入目录String inputPath HDFS /user/hdfs/kmeans/input/;// canopy算法的t1和t2double t1 2;double t2 1;// 收敛阀值double convergenceDelta 0.5;// 最大迭代次数int maxIterations 10;Path output new Path(outputPath);Path input new Path(inputPath);Configuration conf new Configuration();HdfsUtil hdfs new HdfsUtil(HDFS, conf);hdfs.rmr(inputPath);hdfs.mkdirs(inputPath);hdfs.copyFile(localFile, inputPath);hdfs.ls(inputPath);// 每次执行聚类前删除掉上一次的输出目录HadoopUtil.delete(conf, output);// 执行聚类run(conf, input, output, new EuclideanDistanceMeasure(), t1, t2, convergenceDelta, maxIterations);}private static void run(Configuration conf, Path input, Path output,EuclideanDistanceMeasure euclideanDistanceMeasure, double t1, double t2,double convergenceDelta, int maxIterations) throws Exception {Path directoryContainingConvertedInput new Path(output, data);System.out.println(Preparing Input);// 将输入文件序列化并选取RandomAccessSparseVector作为保存向量的数据结构InputDriver.runJob(input, directoryContainingConvertedInput,org.apache.mahout.math.RandomAccessSparseVector);System.out.println(Running Canopy to get initial clusters);// 保存canopy的目录Path canopyOutput new Path(output, canopies);// 执行Canopy聚类CanopyDriver.run(conf, directoryContainingConvertedInput, canopyOutput,euclideanDistanceMeasure, t1, t2, false, 0.0, false);System.out.println(Running KMeans);// 执行k-means聚类并使用canopy目录KMeansDriver.run(conf, directoryContainingConvertedInput,new Path(canopyOutput, Cluster.INITIAL_CLUSTERS_DIR -final),output, convergenceDelta, maxIterations, true, 0.0, false);System.out.println(run clusterdumper);// 将聚类的结果输出至HDFSClusterDumper clusterDumper new ClusterDumper(new Path(output, clusters-*-final),new Path(output, clusteredPoints));clusterDumper.printClusters(null);}
}
在KmeansMahout类上点击右键并执行程序 执行结果在HDFS目录中 5.解析聚类结果
从Mahout的输出目录下提取出所要的信息 编写ClusterOutput类解析聚类后结果
package com;import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.SequenceFile;
import org.apache.mahout.clustering.classify.WeightedPropertyVectorWritable;
import org.apache.mahout.math.Vector;import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;public class ClusterOutput {private static final String HDFS hdfs://master:9000;public static void main(String[] args) {try {// 需要被解析的mahout的输出文件String clusterOutputPath /user/hdfs/kmeans/output;// 解析后的聚类结果将输出至本地磁盘String resultPath /home/data/result.txt;BufferedWriter bw;Configuration conf new Configuration();conf.set(fs.default.name, HDFS);FileSystem fs FileSystem.get(conf);SequenceFile.Reader reader null;reader new SequenceFile.Reader(fs, new Path(clusterOutputPath /clusteredPoints/part-m-00000), conf);bw new BufferedWriter(new FileWriter(new File(resultPath)));// key为聚簇中心IDIntWritable key new IntWritable();WeightedPropertyVectorWritable value new WeightedPropertyVectorWritable();while (reader.next(key, value)) {// 得到向量Vector vector value.getVector();String vectorValue ;// 将向量各个维度拼接成一行用\t分隔for (int i 0; i vector.size(); i) {if (i vector.size() - 1) {vectorValue vector.get(i);} else {vectorValue vector.get(i) \t;}}bw.write(key.toString() \t vectorValue \n\n);}bw.flush();reader.close();} catch (Exception e) {e.printStackTrace();}}
}
在ClusterOutput类上右键执行程序 执行结果被保存在/home/data/result.txt文件中打开终端执行以下命令 6.评估聚类效果
编写InterClusterDistances类计算平均簇间距离
package com;import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.SequenceFile;
import org.apache.hadoop.io.Writable;
import org.apache.mahout.clustering.Cluster;
import org.apache.mahout.clustering.iterator.ClusterWritable;
import org.apache.mahout.common.distance.DistanceMeasure;
import org.apache.mahout.common.distance.EuclideanDistanceMeasure;import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;public class InterClusterDistances {private static final String HDFS hdfs://master:9000;public static void main(String[] args) throws Exception {String inputFile HDFS /user/hdfs/kmeans/output;System.out.println(聚类结果文件地址 inputFile);Configuration conf new Configuration();Path path new Path(inputFile /clusters-2-final/part-r-00000);System.out.println(Input Path path);FileSystem fs FileSystem.get(path.toUri(), conf);ListCluster clusters new ArrayListCluster();SequenceFile.Reader reader new SequenceFile.Reader(fs, path, conf);Writable key (Writable) reader.getKeyClass().newInstance();ClusterWritable value (ClusterWritable) reader.getValueClass().newInstance();while (reader.next(key, value)) {Cluster cluster value.getValue();clusters.add(cluster);value (ClusterWritable) reader.getValueClass().newInstance();}System.out.println(Cluster In Total clusters.size());DistanceMeasure measure new EuclideanDistanceMeasure();double max 0;double min Double.MAX_VALUE;double sum 0;int count 0;SetDouble total new HashSetDouble();// 如果聚类的个数大于1才开始计算if (clusters.size() ! 1 clusters.size() ! 0) {for (int i 0; i clusters.size(); i) {for (int j 0; j clusters.size(); j) {double d measure.distance(clusters.get(i).getCenter(), clusters.get(j).getCenter());min Math.min(d, min);max Math.max(d, max);total.add(d);sum d;count;}}System.out.println(Maximum Intercluster Distance: max);System.out.println(Minimum Intercluster Distance: min);System.out.println(Average Intercluster Distance: sum / count);for (double d : total) {System.out.print([ d ] );}} else if (clusters.size() 1) {System.out.println(只有一个类无法判断聚类质量);} else if (clusters.size() 0) {System.out.println(聚类失败);}}
}
同样右键执行程序得到下图结果