yes.. thanks for the reply..
On Fri, Oct 25, 2013 at 1:46 PM, Dieter De Witte <drdwi...@gmail.com> wrote:
> The question is also on stackoverflow, the problem is that she divides by
> zero in the second mapper I think. (the logs show that both jobs have a
> data flow..
>
>
> 2013/10/25 Robin East <robin.e...@xense.co.uk>
>
>> Hi
>>
>> Are you sure job1 created output where you expected it and in the format
>> you expect? Have you tested job2 on its own with some hand-crafted test
>> data? Is the output from job1 consistent with your hand-crafted test data
>> for job2?
>>
>> regards
>> On 25 Oct 2013, at 06:46, Anseh Danesh <anseh.dan...@gmail.com> wrote:
>>
>> Hi all.
>>
>> I have a mapreduce program with two jobs. second job's key and value
>> comes from first job output. but I think the second map does not get the
>> result from first job. in other words I think my second job did not read
>> the output of my first job.. what should I do?
>>
>> here is the code:
>>
>> public class dewpoint extends Configured implements Tool
>> {
>> private static final Logger logger =
>> LoggerFactory.getLogger(dewpoint.class);
>>
>> static final String KEYSPACE = "weather";
>> static final String COLUMN_FAMILY = "user";
>> private static final String OUTPUT_PATH1 = "/tmp/intermediate1";
>> private static final String OUTPUT_PATH2 = "/tmp/intermediate2";
>> private static final String OUTPUT_PATH3 = "/tmp/intermediate3";
>> private static final String INPUT_PATH1 = "/tmp/intermediate1";
>>
>> public static void main(String[] args) throws Exception
>> {
>>
>> ToolRunner.run(new Configuration(), new dewpoint(), args);
>> System.exit(0);
>> }
>>
>> ///////////////////////////////////////////////////////////
>>
>> public static class dpmap1 extends Mapper<Map<String, ByteBuffer>,
>> Map<FloatWritable, ByteBuffer>, Text, DoubleWritable>
>> {
>> DoubleWritable val1 = new DoubleWritable();
>> Text word = new Text();
>> String date;
>> float temp;
>> public void map(Map<String, ByteBuffer> keys, Map<FloatWritable,
>> ByteBuffer> columns, Context context) throws IOException,
>> InterruptedException
>> {
>>
>> for (Entry<String, ByteBuffer> key : keys.entrySet())
>> {
>> //System.out.println(key.getKey());
>> if (!"date".equals(key.getKey()))
>> continue;
>> date = ByteBufferUtil.string(key.getValue());
>> word.set(date);
>> }
>>
>>
>> for (Entry<FloatWritable, ByteBuffer> column : columns.entrySet())
>> {
>> if (!"temprature".equals(column.getKey()))
>> continue;
>> temp = ByteBufferUtil.toFloat(column.getValue());
>> val1.set(temp);
>> //System.out.println(temp);
>> }
>> context.write(word, val1);
>> }
>> }
>>
>> ///////////////////////////////////////////////////////////
>>
>> public static class dpred1 extends Reducer<Text, DoubleWritable, Text,
>> DoubleWritable>
>> {
>> public void reduce(Text key, Iterable<DoubleWritable> values, Context
>> context) throws IOException, InterruptedException
>> {
>> double beta = 17.62;
>> double landa = 243.12;
>> DoubleWritable result1 = new DoubleWritable();
>> DoubleWritable result2 = new DoubleWritable();
>> for (DoubleWritable val : values){
>> // System.out.println(val.get());
>> beta *= val.get();
>> landa+=val.get();
>> }
>> result1.set(beta);
>> result2.set(landa);
>>
>> context.write(key, result1);
>> context.write(key, result2);
>> }
>> }
>> ///////////////////////////////////////////////////////////
>>
>> public static class dpmap2 extends Mapper <Text, DoubleWritable, Text,
>> DoubleWritable>{
>>
>> Text key2 = new Text();
>> double temp1, temp2 =0;
>>
>> public void map(Text key, Iterable<DoubleWritable> values, Context
>> context) throws IOException, InterruptedException {
>> String[] sp = values.toString().split("\t");
>> for (int i=0; i< sp.length; i+=4)
>> //key2.set(sp[i]);
>> System.out.println(sp[i]);
>> for(int j=1;j< sp.length; j+=4)
>> temp1 = Double.valueOf(sp[j]);
>> for (int k=3;k< sp.length; k+=4)
>> temp2 = Double.valueOf(sp[k]);
>> context.write(key2, new DoubleWritable(temp2/temp1));
>>
>> }
>> }
>>
>> ///////////////////////////////////////////////////////////
>>
>>
>> public static class dpred2 extends Reducer<Text, DoubleWritable, Text,
>> DoubleWritable>
>> {
>> public void reduce(Text key, Iterable<DoubleWritable> values, Context
>> context) throws IOException, InterruptedException
>> {
>>
>> double alpha = 6.112;
>> double tmp = 0;
>> DoubleWritable result3 = new DoubleWritable();
>> for (DoubleWritable val : values){
>> System.out.println(val.get());
>> tmp = alpha*(Math.pow(Math.E, val.get()));
>>
>> }
>> result3.set(tmp);
>> context.write(key, result3);
>>
>>
>> }
>> }
>>
>>
>> ///////////////////////////////////////////////////////////
>>
>>
>> public int run(String[] args) throws Exception
>> {
>>
>> Job job1 = new Job(getConf(), "DewPoint");
>> job1.setJarByClass(dewpoint.class);
>> job1.setMapperClass(dpmap1.class);
>> job1.setOutputFormatClass(SequenceFileOutputFormat.class);
>> job1.setCombinerClass(dpred1.class);
>> job1.setReducerClass(dpred1.class);
>> job1.setMapOutputKeyClass(Text.class);
>> job1.setMapOutputValueClass(DoubleWritable.class);
>> job1.setOutputKeyClass(Text.class);
>> job1.setOutputValueClass(DoubleWritable.class);
>> FileOutputFormat.setOutputPath(job1, new Path(OUTPUT_PATH1));
>>
>>
>> job1.setInputFormatClass(CqlPagingInputFormat.class);
>>
>> ConfigHelper.setInputRpcPort(job1.getConfiguration(), "9160");
>> ConfigHelper.setInputInitialAddress(job1.getConfiguration(),
>> "localhost");
>> ConfigHelper.setInputColumnFamily(job1.getConfiguration(), KEYSPACE,
>> COLUMN_FAMILY);
>> ConfigHelper.setInputPartitioner(job1.getConfiguration(),
>> "Murmur3Partitioner");
>>
>> CqlConfigHelper.setInputCQLPageRowSize(job1.getConfiguration(), "3");
>> job1.waitForCompletion(true);
>>
>> /***************************************/
>>
>> if (job1.isSuccessful()){
>> Job job2 = new Job(getConf(), "DewPoint");
>> job2.setJarByClass(dewpoint.class);
>> job2.setMapperClass(dpmap2.class);
>> job2.setCombinerClass(dpred2.class);
>> job2.setReducerClass(dpred2.class);
>> job2.setMapOutputKeyClass(Text.class);
>> job2.setMapOutputValueClass(DoubleWritable.class);
>> job2.setOutputKeyClass(Text.class);
>> job2.setOutputValueClass(DoubleWritable.class);
>> job2.setOutputFormatClass(TextOutputFormat.class);
>> job2.setInputFormatClass(SequenceFileInputFormat.class);
>> FileInputFormat.addInputPath(job2, new Path(OUTPUT_PATH1));
>> FileOutputFormat.setOutputPath(job2, new Path(OUTPUT_PATH2));
>> job2.waitForCompletion(true);
>> }
>> ///////////////////////////////////////////////////
>>
>> return 0;
>> }
>> }
>>
>> for example in my second map phase when I do a System.out.println(key) it
>> does not print any thing and in reduce result the value is 'infinity'....
>>
>>
>>
>
