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From manish dunani <manishd...@gmail.com>
Subject Re: [Error]Finding average using hbase hadoop
Date Sat, 17 Aug 2013 07:10:31 GMT
Hey jean,
I did it according to you.
I convert as u told..But still face the same error.

And ted I am new to this don't get an idea how can i use this method..Can
You please show me..?

Your Help will be appreciated..



On Fri, Aug 16, 2013 at 10:04 PM, Ted Yu <yuzhihong@gmail.com> wrote:

> Here is javadoc for toFloat():
>
>    * Presumes float encoded as IEEE 754 floating-point "single format"
>
>    * @param bytes byte array
>
>    * @return Float made from passed byte array.
>
>    */
>
>   public static float toFloat(byte [] bytes) {
>
> So for values of '2.5', toFloat() is not the proper method.
>
> You can float conversion provided by Java.
>
>
> Cheers
>
>
> On Fri, Aug 16, 2013 at 6:57 AM, Ted Yu <yuzhihong@gmail.com> wrote:
>
> > Here is code from Bytes:
> >
> >   public static float toFloat(byte [] bytes, int offset) {
> >
> >     return Float.intBitsToFloat(toInt(bytes, offset, SIZEOF_INT));
> >
> > Looking at your sample data:
> >
> >  2010-02-04           column=stocks:open, timestamp=1376567559424,
> > value=*2.5*
> >
> > The length of value didn't match SIZEOF_INT.
> >
> > It seems you need to validate the values first.
> >
> >
> > Cheers
> >
> >
> > On Fri, Aug 16, 2013 at 3:42 AM, manish dunani <manishd207@gmail.com
> >wrote:
> >
> >> hello,
> >>
> >> I am using apache hadoop 1.1.2 and hbase 0.94.9 on pseudo distibuted
> mode.
> >>
> >> I am trying to find Average open stocks values.
> >>
> >> *sample dataset in hbase::**(table name:nyse4)*
> >>
> >>
> >>  2010-02-04           column=stocks:open, timestamp=1376567559424,
> >> value=2.5
> >>  2010-02-04           column=stocks:symbol, timestamp=1376567559424,
> >> value=QXM
> >>  2010-02-05           column=stocks:open, timestamp=1376567559429,
> >> value=2.42
> >>  2010-02-05           column=stocks:symbol, timestamp=1376567559429,
> >> value=QXM
> >>  2010-02-08           column=stocks:open, timestamp=1376567559431,
> >> value=2.33
> >>  2010-02-08           column=stocks:symbol, timestamp=1376567559431,
> >> value=QXM
> >>
> >> *code:*(please ignores the lines that are commenting)
> >>
> >>
> >> > package com.maddy;
> >> >
> >> > import java.io.IOException;
> >> >
> >> > import org.apache.hadoop.conf.Configuration;
> >> > import org.apache.hadoop.fs.Path;
> >> > import org.apache.hadoop.hbase.HBaseConfiguration;
> >> > import org.apache.hadoop.hbase.client.Put;
> >> > import org.apache.hadoop.hbase.client.Result;
> >> > import org.apache.hadoop.hbase.client.Scan;
> >> > import org.apache.hadoop.hbase.filter.FirstKeyOnlyFilter;
> >> > import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
> >> > import org.apache.hadoop.hbase.mapreduce.TableMapReduceUtil;
> >> > import org.apache.hadoop.hbase.mapreduce.TableMapper;
> >> > import org.apache.hadoop.hbase.mapreduce.TableReducer;
> >> > import org.apache.hadoop.hbase.util.Bytes;
> >> > //import org.apache.hadoop.io.DoubleWritable;
> >> > import org.apache.hadoop.io.FloatWritable;
> >> > import org.apache.hadoop.mapreduce.Job;
> >> > import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
> >> >
> >> >
> >> > public class openaveragestock
> >> > {
> >> >     public static class map extends
> >> > TableMapper<ImmutableBytesWritable,FloatWritable>
> >> >     {
> >> >         @Override
> >> >
> >> >         public void map(ImmutableBytesWritable row,Result
> value,Context
> >> > context) throws IOException
> >> >         {
> >> >
> >> >             byte[]
> >> > val=(value.getValue("stocks".getBytes(),"open".getBytes()));
> >> >             //byte[]
> >> > val1=(value.getValue("stocks".getBytes(),"symbol".getBytes()));
> >> >
> >> >
> >> >             ImmutableBytesWritable stock_symbol=new
> >> > ImmutableBytesWritable("symbol".getBytes());
> >> >
> >> >
> >> >             try
> >> >             {
> >> >                 context.write(stock_symbol,new
> >> > FloatWritable(Bytes.toFloat(val)));
> >> >             }
> >> >             catch(InterruptedException e)
> >> >
> >> >             {
> >> >                  throw new IOException(e);
> >> >             }
> >> >
> >> >
> >> >         }
> >> >
> >> >
> >> >     }
> >> >
> >> >
> >> >     public static class reduce extends
> >> >
> >>
> TableReducer<ImmutableBytesWritable,FloatWritable,ImmutableBytesWritable>
> >> >     {
> >> >
> >> >         @Override
> >> >         public void reduce(ImmutableBytesWritable
> >> > key,Iterable<FloatWritable>values,Context context) throws IOException,
> >> > InterruptedException
> >> >         {
> >> >             float sum=0;
> >> >             int count=0;
> >> >           //  float average=0;
> >> >             for(FloatWritable val:values)
> >> >             {
> >> >                 sum+=val.get();
> >> >                 count++;
> >> >             }
> >> >             //average=(sum/count);
> >> >             Put put=new Put(key.get());
> >> >
> >> >
> >>
> put.add(Bytes.toBytes("stocks_output"),Bytes.toBytes("average"),Bytes.toBytes(sum/count));
> >> >             System.out.println("For\t"+count+"\t average
> >> is:"+(sum/count));
> >> >             context.write(key,put);
> >> >
> >> >         }
> >> >
> >> >     }
> >> >
> >> >     public static void main(String args[]) throws IOException,
> >> > ClassNotFoundException, InterruptedException
> >> >     {
> >> >         Configuration config=HBaseConfiguration.create();
> >> >         config.addResource("/home/manish/workspace/hbase
> >> > project/bin/hbase-site.xml");
> >> >         Job job=new Job(config,"openstockaverage1");
> >> >
> >> >
> >> >         Scan scan=new Scan();
> >> >         scan.addFamily("stocks".getBytes());
> >> >         scan.setFilter(new FirstKeyOnlyFilter());
> >> >
> >> >         TableMapReduceUtil.initTableMapperJob("nyse4",
> >> >                 scan,
> >> >                 map.class,
> >> >                 ImmutableBytesWritable.class,
> >> >                 FloatWritable.class,
> >> >                 job);
> >> >
> >> >         TableMapReduceUtil.initTableReducerJob("nyse5",
> >> >                 reduce.class,
> >> >                 job);
> >> >         //job.setReducerClass(reduce.class);
> >> >
> >> >         FileOutputFormat.setOutputPath(job, new Path(
> >> >
> >> "hdfs://localhost:54310/user/manish/edurekahbasehadoop1"));
> >> >         job.waitForCompletion(true);
> >> >     }
> >> >
> >> > }
> >> >
> >> >
> >> >
> >> > *===>Got stuck into error:*
> >> >
> >> >
> >> > 13/08/16 03:21:45 INFO mapred.JobClient: Running job: job_local_0001
> >> > 13/08/16 03:21:46 INFO mapred.JobClient:  map 0% reduce 0%
> >> > 13/08/16 03:21:46 INFO mapreduce.TableOutputFormat: Created table
> >> instance
> >> > for nyse5
> >> > 13/08/16 03:21:46 INFO util.ProcessTree: setsid exited with exit code
> 0
> >> > 13/08/16 03:21:47 INFO mapred.Task:  Using ResourceCalculatorPlugin :
> >> > org.apache.hadoop.util.LinuxResourceCalculatorPlugin@50b77c
> >> > 13/08/16 03:21:47 INFO mapred.MapTask: io.sort.mb = 100
> >> > 13/08/16 03:21:53 INFO mapred.MapTask: data buffer = 79691776/99614720
> >> > 13/08/16 03:21:53 INFO mapred.MapTask: record buffer = 262144/327680
> >> > 13/08/16 03:21:54 WARN mapred.LocalJobRunner: job_local_0001
> >> > java.lang.IllegalArgumentException: offset (0) + length (4) exceed the
> >> > capacity of the array: 3
> >> >     at
> >> >
> >>
> org.apache.hadoop.hbase.util.Bytes.explainWrongLengthOrOffset(Bytes.java:543)
> >> >     at org.apache.hadoop.hbase.util.Bytes.toInt(Bytes.java:690)
> >> >     at org.apache.hadoop.hbase.util.Bytes.toFloat(Bytes.java:584)
> >> >     at org.apache.hadoop.hbase.util.Bytes.toFloat(Bytes.java:574)
> >> >     at com.maddy.openaveragestock$map.map(openaveragestock.java:41)
> >> >     at com.maddy.openaveragestock$map.map(openaveragestock.java:1)
> >> >     at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144)
> >> >     at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:764)
> >> >     at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370)
> >> >     at
> >> >
> org.apache.hadoop.mapred.LocalJobRunner$Job.run(LocalJobRunner.java:214)
> >> >
> >> >
> >> I cannot find where is it fail??
> >> Can you please tell me??
> >> where i was wrong..?
> >>
> >>
> >> Your help will be appreciated.
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >> --
> >> Regards
> >>
> >> *Manish Dunani*
> >> *Contact No* : +91 9408329137
> >> *skype id* : manish.dunani*
> >> *
> >>
> >
> >
>



-- 
Regards

*Manish Dunani*
*Contact No* : +91 9408329137
*skype id* : manish.dunani*
*

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