I believe it is supposed to, at least at the high level.  We don't have any 1-1 
tests, so YMMV.


On Dec 17, 2011, at 8:26 PM, Lance Norskog wrote:

> Does the new approach do the same thing as the old approach?
> 
> On Thu, Dec 15, 2011 at 1:56 AM, Daniele Volpi <danielevo...@gmail.com> wrote:
>> Yes Grant that was the point of my first question..
>> Now I'll take a look at the vector implementation.
>> Thanks again
>> Daniele
>> 
>> On 14 December 2011 23:44, Grant Ingersoll <gsing...@apache.org> wrote:
>>> While Ted answered the Dissector question, your original issue, I believe, 
>>> is that Mahout currently has two different NB implementations.  
>>> trainclassifier/testclassifier use the old, word based package which 
>>> requires Text as input.  The new package, which TrainNaiveBayesJob uses, 
>>> requires VectorWritables.  For the latter case, you don't use the 
>>> BayesFileFormatter at all.  See the asf-email-examples for how to use the 
>>> Vector based approach.  I realize this is confusing, but we haven't yet 
>>> made the transition fully to the new vector based approach.
>>> 
>>> -Grant
>>> 
>>> On Dec 14, 2011, at 3:01 AM, Daniele Volpi wrote:
>>> 
>>>> The version is 0.6-SNAPSHOT
>>>> From terminal both commands trainclassifier and testclassifier work.
>>>> Actually my real purpose is to use the TrainNaiveBayesJob in order to
>>>> obtain a StandardNaiveBayesClassifier that i can use with the
>>>> ModelDissector class similiar to chapter 15 in Mahout In Action, maybe the
>>>> procedure is completely wrong.
>>>> Thank you
>>>> 
>>>> 
>>>> On 14 December 2011 01:24, Ted Dunning <ted.dunn...@gmail.com> wrote:
>>>> 
>>>>> Which version of Mahout?
>>>>> 
>>>>> And what happens when you train the classifier from the command line?
>>>>> 
>>>>> On Tue, Dec 13, 2011 at 2:27 PM, Daniele Volpi <danielevo...@gmail.com
>>>>>> wrote:
>>>>> 
>>>>>> First of all i've converted the train files in the format:
>>>>>> target[\t]terms
>>>>>> through the BayesFileFormatter class.
>>>>>> Then i've converted these files (one per category) in SequenceFile using
>>>>>> the seqdirectory program.
>>>>>> After that I ran this code:
>>>>>> 
>>>>>> TrainNaiveBayesJob trainer = new TrainNaiveBayesJob();
>>>>>> trainer.setConf(new Configuration());
>>>>>> 
>>>>>> String[] params = {"-i" + inputPath, "-o" + outputPath, "-ow", "-el"};
>>>>>> trainer.run(params);
>>>>>> 
>>>>>> Here's the error message:
>>>>>> 
>>>>>> java.lang.ClassCastException: org.apache.hadoop.io.Text cannot be cast to
>>>>>> org.apache.mahout.math.VectorWritable
>>>>>> at
>>>>>> 
>>>>>> 
>>>>> org.apache.mahout.classifier.naivebayes.training.IndexInstancesMapper.map(IndexInstancesMapper.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:212)
>>>>>> 
>>>>>> On 13 December 2011 19:52, Grant Ingersoll <gsing...@apache.org> wrote:
>>>>>> 
>>>>>>> What steps have you done?
>>>>>>> 
>>>>>>> On Dec 13, 2011, at 12:29 PM, Daniele Volpi wrote:
>>>>>>> 
>>>>>>>> Hi everyone,
>>>>>>>> I'm trying to implement the Naive Bayes classifier through the
>>>>>>>> TrainNaiveBayesJob class.
>>>>>>>> After convert the text files in the required sequencefile for the
>>>>> "run"
>>>>>>>> method through the seqdirectory program i get this error:
>>>>>>>> 
>>>>>>>> java.lang.ClassCastException: org.apache.hadoop.io.Text cannot be
>>>>> cast
>>>>>> to
>>>>>>>> org.apache.mahout.math.VectorWritable
>>>>>>>> 
>>>>>>>> Do you have some hints on the right usage of this class?
>>>>>>>> 
>>>>>>>> Thanks,
>>>>>>>> Daniele Volpi
>>>>>>> 
>>>>>>> --------------------------------------------
>>>>>>> Grant Ingersoll
>>>>>>> http://www.lucidimagination.com
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>> 
>>>>> 
>>> 
>>> --------------------------------------------
>>> Grant Ingersoll
>>> http://www.lucidimagination.com
>>> 
>>> 
>>> 
> 
> 
> 
> -- 
> Lance Norskog
> goks...@gmail.com

--------------------------
Grant Ingersoll
http://www.lucidimagination.com





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