Looks like the input file's format isn't right. It's expecting that funky "::"-delimited file. What is the input like?
The error message sure could be better, I can fix that. On Fri, Sep 24, 2010 at 4:54 PM, web service <[email protected]> wrote: > How do I run examples listed at > https://cwiki.apache.org/MAHOUT/recommendationexamples.html > > I downloaded the file for grouplens dataset and after running the command, I > get back an error - > [code] > > mvn -e exec:java > -Dexec.mainClass="org.apache.mahout.cf.taste.example.grouplens.GroupLensRecommenderEvaluatorRunner" > -Dexec.args="-i > ~/software/hadoop/mahout/mahout-0.3/examples/input/ml-data/u.data" > > > > ................. > Caused by: java.lang.StringIndexOutOfBoundsException: String index out of > range: -1 > at java.lang.String.substring(String.java:1937) > at > org.apache.mahout.cf.taste.example.grouplens.GroupLensDataModel.convertGLFile(GroupLensDataModel.java:61) > at > org.apache.mahout.cf.taste.example.grouplens.GroupLensDataModel.<init>(GroupLensDataModel.java:48) > at > org.apache.mahout.cf.taste.example.grouplens.GroupLensRecommenderEvaluatorRunner.main(GroupLensRecommenderEvaluatorRunner.java:49) > > [/code] > > > -Mac >
