Код: Выделить всё
Calgary,AB,2009-01-07,604680,12694,2.5207754,0.065721168,0.025668362,0.972051954,0.037000279,0.022319018,,,0.003641149,,,0.002936745,,,0.016723641< /code> < /p>
И выход должен быть чем -то вроде:
Calgary 2009 Average is: Max: Min: И вот мой код, который дает файл TXT и вычисляет AVG, Min и Max:
public class AverageMinMax {
public static class Map extends Mapper {
//private static final FloatWritable rep= new FloatWritable(1);
public void map(LongWritable key,Text value,Context context)
throws IOException, InterruptedException {
context.write(new Text("Map_Output"), value);
};
}
public static class Combiner extends Reducer
{
public void reduce(Text key,Iterable values,Context context) throws IOException,InterruptedException
{
Integer NumberOfValues=0;
double sum=0D;
double min=0D;
double max=0D;
//double min=values.get(0);
Iterator itr = values.iterator();
//convertString=values(0);
while(itr.hasNext())
{
String TexttoString = itr.next().toString();
Double value = Double.parseDouble(TexttoString);
if(valuemax)
{
max=value;
}
NumberOfValues++;
sum+=value;
}
Double average = sum/NumberOfValues;
context.write(new Text("Combiner_output"), new Text(average + "," + NumberOfValues+","+min+","+max));
};
}
public static class Reduce extends
Reducer {
public void reduce(Text key, Iterable values,
Context context) throws IOException, InterruptedException {
Integer totalNumberOfValues= 0;
Double sum=0.00;
Double min=0D;
Double max=0D;
Iterator itr = values.iterator();
while(itr.hasNext())
{
String TexttoString = itr.next().toString();
String[] split_String = TexttoString.split(",");
Double average = Double.parseDouble(split_String[0]);
Integer NumberOfValues = Integer.parseInt(split_String[1]);
Double minValue=Double.parseDouble(split_String[2]);
Double maxValue=Double.parseDouble(split_String[3]);
if(minValuemax)
{
max=maxValue;
}
sum+=(average*NumberOfValues);
totalNumberOfValues+=NumberOfValues;
}
Double average= sum/totalNumberOfValues;
context.write(new Text("Average and Minimum and Max is"), new Text(average.toString()+" and "+ min.toString()+" and "+ max.toString()));
};
}
public static void main(String[] args) throws Exception {
Configuration conf = new Configuration();
Job job=new Job(conf,"AverageMinMax.class");
job.setJarByClass(AverageMinMax.class);
job.setJobName("MapReduceAssignment");
//JobConf conf = new JobConf(Hadoop_map_reduce.class);
//conf.setJobName("Hadoop_assignment");
// Configuration conf = new Configuration();
//Job job = new Job(conf, "maxmin");
//job.setJarByClass(Hadoop_map_reduce.class);
// FileSystem fs = FileSystem.get(conf);
/* if (fs.exists(new Path(args[1]))) {
fs.delete(new Path(args[1]), true);
}*/
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(Text.class);
//job.setNumReduceTasks(1);
job.setMapperClass(Map.class);
job.setReducerClass(Reduce.class);
job.setCombinerClass(Combiner.class);
job.setInputFormatClass(TextInputFormat.class);
job.setOutputFormatClass(TextOutputFormat.class);
FileInputFormat.addInputPath(job, new Path(args[0]));
// FileOutputFormat.setOutputPath(job, new Path(args[1]));
//FileInputFormat.addInputPath(job, new Path("/home/cloudera/Desktop/assign2"));
FileOutputFormat.setOutputPath(job, new Path(args[1]));
// FileOutputFormat.setOutputPath(job, new Path(" user/cloudera/output"));
job.waitForCompletion(true);
}
}
< /code>
Итак, моя первая проблема в том, что я не знаю, как преобразовать дату в Mapper и как найти 2 клавиши и показать в выводе. Я имею в виду, как переписать этот код!
Я ценю вашу помощь
Подробнее здесь: https://stackoverflow.com/questions/364 ... ith-2-keys
