Item Recommendation mahout Java error - macos

Question

I'm trying to make an item based recommendation but i got this error:
Lore:~ lorenzoferri$ mahout parallelALS --input prova1.csv --output output.csv --lambda 0.1 --implicitFeedback true --alpha 0.8 --numFeatures 2 --numIterations 5 --numThreadsPerSolver 1 --tempDir tmp
No MAHOUT_CONF_DIR found
Running on hadoop, using /usr/local/bin/hadoop and HADOOP_CONF_DIR=
MAHOUT-JOB: /usr/local/Cellar/mahout/0.9/libexec/mahout-examples-0.9-job.jar
15/02/09 17:32:25 WARN driver.MahoutDriver: No parallelALS.props found on classpath, will use command-line arguments only
15/02/09 17:32:26 INFO common.AbstractJob: Command line arguments: {--alpha=[0.8], --endPhase=[2147483647], --implicitFeedback=[true], --input=[prova1.csv], --lambda=[0.1], --numFeatures=[2], --numIterations=[5], --numThreadsPerSolver=[1], --output=[output.csv], --startPhase=[0], --tempDir=[tmp]}
15/02/09 17:32:26 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
15/02/09 17:32:26 INFO Configuration.deprecation: mapred.input.dir is deprecated. Instead, use mapreduce.input.fileinputformat.inputdir
15/02/09 17:32:26 INFO Configuration.deprecation: mapred.compress.map.output is deprecated. Instead, use mapreduce.map.output.compress
15/02/09 17:32:26 INFO Configuration.deprecation: mapred.output.dir is deprecated. Instead, use mapreduce.output.fileoutputformat.outputdir
Exception in thread "main" java.lang.IncompatibleClassChangeError: Found interface org.apache.hadoop.mapreduce.JobContext, but class was expected
at org.apache.mahout.common.HadoopUtil.getCustomJobName(HadoopUtil.java:174)
at org.apache.mahout.common.AbstractJob.prepareJob(AbstractJob.java:614)
at org.apache.mahout.cf.taste.hadoop.als.ParallelALSFactorizationJob.run(ParallelALSFactorizationJob.java:166)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:84)
at org.apache.mahout.cf.taste.hadoop.als.ParallelALSFactorizationJob.main(ParallelALSFactorizationJob.java:113)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:71)
at org.apache.hadoop.util.ProgramDriver.run(ProgramDriver.java:144)
at org.apache.hadoop.util.ProgramDriver.driver(ProgramDriver.java:152)
at org.apache.mahout.driver.MahoutDriver.main(MahoutDriver.java:195)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at org.apache.hadoop.util.RunJar.run(RunJar.java:221)
at org.apache.hadoop.util.RunJar.main(RunJar.java:136)
Lore:~ lorenzoferri$
I also tried:
Lore:~ lorenzoferri$ mahout recommenditembased -i '/Users/lorenzoferri/Desktop/prova1.csv' -o '/Users/lorenzoferri/Desktop/output.csv' -n 100 -s SIMILARITY_COOCCURRENCE
No MAHOUT_CONF_DIR found
Running on hadoop, using /usr/local/bin/hadoop and HADOOP_CONF_DIR=
MAHOUT-JOB: /usr/local/Cellar/mahout/0.9/libexec/mahout-examples-0.9-job.jar
15/02/09 17:37:02 WARN driver.MahoutDriver: No recommenditembased.props found on classpath, will use command-line arguments only
15/02/09 17:37:02 INFO common.AbstractJob: Command line arguments: {--booleanData=[false], --endPhase=[2147483647], --input=[/Users/lorenzoferri/Desktop/prova1.csv], --maxPrefsInItemSimilarity=[500], --maxPrefsPerUser=[10], --maxSimilaritiesPerItem=[100], --minPrefsPerUser=[1], --numRecommendations=[100], --output=[/Users/lorenzoferri/Desktop/output.csv], --similarityClassname=[SIMILARITY_COOCCURRENCE], --startPhase=[0], --tempDir=[temp]}
15/02/09 17:37:02 INFO common.AbstractJob: Command line arguments: {--booleanData=[false], --endPhase=[2147483647], --input=[/Users/lorenzoferri/Desktop/prova1.csv], --minPrefsPerUser=[1], --output=[temp/preparePreferenceMatrix], --ratingShift=[0.0], --startPhase=[0], --tempDir=[temp]}
15/02/09 17:37:03 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
15/02/09 17:37:03 INFO Configuration.deprecation: mapred.input.dir is deprecated. Instead, use mapreduce.input.fileinputformat.inputdir
15/02/09 17:37:03 INFO Configuration.deprecation: mapred.compress.map.output is deprecated. Instead, use mapreduce.map.output.compress
15/02/09 17:37:03 INFO Configuration.deprecation: mapred.output.dir is deprecated. Instead, use mapreduce.output.fileoutputformat.outputdir
Exception in thread "main" java.lang.IncompatibleClassChangeError: Found interface org.apache.hadoop.mapreduce.JobContext, but class was expected
at org.apache.mahout.common.HadoopUtil.getCustomJobName(HadoopUtil.java:174)
at org.apache.mahout.common.AbstractJob.prepareJob(AbstractJob.java:614)
at org.apache.mahout.cf.taste.hadoop.preparation.PreparePreferenceMatrixJob.run(PreparePreferenceMatrixJob.java:73)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.mahout.cf.taste.hadoop.item.RecommenderJob.run(RecommenderJob.java:164)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.mahout.cf.taste.hadoop.item.RecommenderJob.main(RecommenderJob.java:322)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:71)
at org.apache.hadoop.util.ProgramDriver.run(ProgramDriver.java:144)
at org.apache.hadoop.util.ProgramDriver.driver(ProgramDriver.java:152)
at org.apache.mahout.driver.MahoutDriver.main(MahoutDriver.java:195)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at org.apache.hadoop.util.RunJar.run(RunJar.java:221)
at org.apache.hadoop.util.RunJar.main(RunJar.java:136)
I installed mahout via brew, on mac os x 10.10, but i got the same problem on ubuntu. On the web i can only find tutorial on eclipse, but i would like to run it through the terminal.

Answer 1

No MAHOUT_CONF_DIR found
add to your .bash_profile or .zshrc:
export MAHOUT=/path/to/mahout
export MAHOUT_CONF_DIR=$MAHOUT_HOME/conf
In order to run Mahout locally
add to your .bash_profile or .zshrc:
export MAHOUT_LOCAL="not-an-empty-string"
set to anything other than an empty string to force mahout to run locally
even if HADOOP_CONF_DIRand HADOOP_HOME are set.
In order to get up and running quickly I will recommend for you to:
Download mahout as a tar.gz: http://apache.mivzakim.net/mahout/0.9/mahout-distribution-0.9.tar.gz
Follow steps 1 and 2 as mentioned, the /path/to/mahout is where you extracted mahout-distribution-0.9
Run the mahout command from mahout-distribution-0.9/bin/mahout
i.e: ./bin/mahout recommenditembased -i '/Users/lorenzoferri/Desktop/prova1.csv' -o '/Users/lorenzoferri/Desktop/output.csv' -n 100 -s SIMILARITY_COOCCURRENCE
In mahout-distribution-0.9/examples you can run and explore some shell scripts
https://svn.apache.org/repos/asf/mahout/trunk/bin/mahout