import org.apache.hadoop.io.*;
import org.apache.hadoop.mapreduce.Mapper;
import java.io.IOException;
public class Movie8Mapper extends Mapper<LongWritable,Text,Text, DoubleWritable> {
@Override
protected void map(LongWritable key,Text value,Context context) throws IOException,InterruptedException{
//super.map(key,value,context);
String line=value.toString(); //[0 芳华 9.1 http://maoyan.com/films/1170264 剧情,爱情,战争 中国大陆 大陆上映 136 2017]
String[] arr=line.split("\00");
String year=line.substring(line.length()-4); //从后往前读取
double time=0;
if (arr.length>7){
time=Double.parseDouble(arr[7]);
// System.out.println(time);
context.write(new Text(year),new DoubleWritable(time));
}
}
}
import org.apache.hadoop.io.DoubleWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Reducer;
import java.io.IOException;
import org.apache.hadoop.io.DoubleWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Reducer;
import java.io.IOException;
public class Movie8Reducer extends Reducer<Text, DoubleWritable,Text,DoubleWritable> {
@Override
protected void reduce(Text key, Iterable<DoubleWritable> values, Context context) throws IOException, InterruptedException {
//super.reduce(key, values, context);
double sum=0;
double sc=0;
double avg_time;
for (DoubleWritable i:values){
sum+=i.get();
sc++;
}
String str=String.format("%.2f",sum/sc); //保留两位小数
avg_time=Double.parseDouble(str);
context.write(key,new DoubleWritable(avg_time));
}
}
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.DoubleWritable;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import java.io.FileOutputStream;
import java.io.IOException;
public class Movie8Runner {
public static void main(String[] args) throws IOException, ClassNotFoundException, InterruptedException {
Configuration conf=new Configuration();
//创建job
Job job= Job.getInstance(conf,"maoyan");
//设置输入输出路径
FileInputFormat.addInputPath(job,new Path(args[0]));
FileOutputFormat.setOutputPath(job,new Path(args[1]));
//设置运行类
job.setJarByClass(Movie8Runner.class);
job.setMapperClass(Movie8Mapper.class);
job.setReducerClass(Movie8Reducer.class);
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(DoubleWritable.class);
System.exit(job.waitForCompletion(true)?0:1);
}
}
import pandas as pd
import matplotlib
import matplotlib.pyplot as plt
matplotlib.rcParams['font.family']='SimHei'
matplotlib.rcParams['font.sans-serif'] = ['SimHei']
data=pd.read_csv(r"E:\output8\part-r-00000",sep='\t',header=None)
data.columns=['年份','上映电影平均时长']
data.head()
plt.figure(figsize=(9,6))
x=data['年份']
y=data['上映电影平均时长']
plt.plot(x,y,color='r',label='均值')
plt.xlabel('上映时间')
plt.ylabel("平均时长")
# plt.xticks(rotation=30,fontsize=10)
plt.xlim(1980,2017)
plt.legend()
plt.title("上映电影平均时长趋势表")
plt.show()