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Posted to user@mahout.apache.org by jung hoon sohn <js...@gmail.com> on 2012/09/15 09:29:30 UTC

KmeansDriver Question

Hello, I am trying to cluster the input data using KmeansDriver.
The input vector is transformed from the lucene vector using the
"bin/mahout lucene.vector ..." commands and when I run the
KmeansDriver using the run method, I get

12/09/15 15:18:13 INFO mapred.JobClient: Task Id :
attempt_201209121951_0067_m_000000_1, Status : FAILED
java.lang.ClassCastException: org.apache.hadoop.io.LongWritable cannot be
cast to org.apache.hadoop.io.Text
        at
org.apache.mahout.vectorizer.document.SequenceFileTokenizerMapper.map(SequenceFileTokenizerMapper.java:37)
        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.Child$4.run(Child.java:255)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:415)
        at
org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1093)
        at org.apache.hadoop.mapred.Child.main(Child.java:249)

for several attempts but the process goes on and generates the output data.
I can even run the clusterdump using the output cluster data however I am
concerned about the effect of above errors.

Please help me to get through the problem.

Thanks.

Jung Hoon

Re: KmeansDriver Question

Posted by Paritosh Ranjan <pr...@xebia.com>.
AFAIK SequenceFileTokenizerMapper is not called from KMeansdriver.

The mapper is tokenizing sequence files, so, the error might be during 
that step.

On 17-09-2012 12:39, jung hoon sohn wrote:
> Thank you for the reply.
> However the error was thrown during the process of the map (
> org.apache.hadoop.mapreduce.**Mapper.run).
> Isn't the mapping function part of the KmeansDriver class?
>
> Thank You.
>
> Jung Hoon
>
> On Sat, Sep 15, 2012 at 5:48 PM, Paritosh Ranjan <pr...@xebia.com> wrote:
>
>> I don't think that it is a kmeans driver error.
>> SequenceFileTokenizerMapper is not used in KmeansDriver. I think you are
>> getting error while transforming data.
>>
>>
>> On 15-09-2012 12:59, jung hoon sohn wrote:
>>
>>> Hello, I am trying to cluster the input data using KmeansDriver.
>>> The input vector is transformed from the lucene vector using the
>>> "bin/mahout lucene.vector ..." commands and when I run the
>>> KmeansDriver using the run method, I get
>>>
>>> 12/09/15 15:18:13 INFO mapred.JobClient: Task Id :
>>> attempt_201209121951_0067_m_**000000_1, Status : FAILED
>>> java.lang.ClassCastException: org.apache.hadoop.io.**LongWritable cannot
>>> be
>>> cast to org.apache.hadoop.io.Text
>>>           at
>>> org.apache.mahout.vectorizer.**document.**SequenceFileTokenizerMapper.**
>>> map(**SequenceFileTokenizerMapper.**java:37)
>>>           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.**Child$4.run(Child.java:255)
>>>           at java.security.**AccessController.doPrivileged(**Native
>>> Method)
>>>           at javax.security.auth.Subject.**doAs(Subject.java:415)
>>>           at
>>> org.apache.hadoop.security.**UserGroupInformation.doAs(**
>>> UserGroupInformation.java:**1093)
>>>           at org.apache.hadoop.mapred.**Child.main(Child.java:249)
>>>
>>> for several attempts but the process goes on and generates the output
>>> data.
>>> I can even run the clusterdump using the output cluster data however I am
>>> concerned about the effect of above errors.
>>>
>>> Please help me to get through the problem.
>>>
>>> Thanks.
>>>
>>> Jung Hoon
>>>
>>>
>>

Re: KmeansDriver Question

Posted by jung hoon sohn <js...@gmail.com>.
Thank you for the reply.
However the error was thrown during the process of the map (
org.apache.hadoop.mapreduce.**Mapper.run).
Isn't the mapping function part of the KmeansDriver class?

Thank You.

Jung Hoon

On Sat, Sep 15, 2012 at 5:48 PM, Paritosh Ranjan <pr...@xebia.com> wrote:

> I don't think that it is a kmeans driver error.
> SequenceFileTokenizerMapper is not used in KmeansDriver. I think you are
> getting error while transforming data.
>
>
> On 15-09-2012 12:59, jung hoon sohn wrote:
>
>> Hello, I am trying to cluster the input data using KmeansDriver.
>> The input vector is transformed from the lucene vector using the
>> "bin/mahout lucene.vector ..." commands and when I run the
>> KmeansDriver using the run method, I get
>>
>> 12/09/15 15:18:13 INFO mapred.JobClient: Task Id :
>> attempt_201209121951_0067_m_**000000_1, Status : FAILED
>> java.lang.ClassCastException: org.apache.hadoop.io.**LongWritable cannot
>> be
>> cast to org.apache.hadoop.io.Text
>>          at
>> org.apache.mahout.vectorizer.**document.**SequenceFileTokenizerMapper.**
>> map(**SequenceFileTokenizerMapper.**java:37)
>>          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.**Child$4.run(Child.java:255)
>>          at java.security.**AccessController.doPrivileged(**Native
>> Method)
>>          at javax.security.auth.Subject.**doAs(Subject.java:415)
>>          at
>> org.apache.hadoop.security.**UserGroupInformation.doAs(**
>> UserGroupInformation.java:**1093)
>>          at org.apache.hadoop.mapred.**Child.main(Child.java:249)
>>
>> for several attempts but the process goes on and generates the output
>> data.
>> I can even run the clusterdump using the output cluster data however I am
>> concerned about the effect of above errors.
>>
>> Please help me to get through the problem.
>>
>> Thanks.
>>
>> Jung Hoon
>>
>>
>
>

Re: KmeansDriver Question

Posted by Paritosh Ranjan <pr...@xebia.com>.
I don't think that it is a kmeans driver error. 
SequenceFileTokenizerMapper is not used in KmeansDriver. I think you are 
getting error while transforming data.

On 15-09-2012 12:59, jung hoon sohn wrote:
> Hello, I am trying to cluster the input data using KmeansDriver.
> The input vector is transformed from the lucene vector using the
> "bin/mahout lucene.vector ..." commands and when I run the
> KmeansDriver using the run method, I get
>
> 12/09/15 15:18:13 INFO mapred.JobClient: Task Id :
> attempt_201209121951_0067_m_000000_1, Status : FAILED
> java.lang.ClassCastException: org.apache.hadoop.io.LongWritable cannot be
> cast to org.apache.hadoop.io.Text
>          at
> org.apache.mahout.vectorizer.document.SequenceFileTokenizerMapper.map(SequenceFileTokenizerMapper.java:37)
>          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.Child$4.run(Child.java:255)
>          at java.security.AccessController.doPrivileged(Native Method)
>          at javax.security.auth.Subject.doAs(Subject.java:415)
>          at
> org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1093)
>          at org.apache.hadoop.mapred.Child.main(Child.java:249)
>
> for several attempts but the process goes on and generates the output data.
> I can even run the clusterdump using the output cluster data however I am
> concerned about the effect of above errors.
>
> Please help me to get through the problem.
>
> Thanks.
>
> Jung Hoon
>