And it's like this issue: https://issues.apache.org/jira/browse/MAHOUT-367
On Mon, Sep 27, 2010 at 10:36 AM, Sam Yang <[email protected]> wrote: > But I got this when no preference data: > ====== > > java.lang.IllegalArgumentException: size is less than 1 > > at org.apache.mahout.cf.taste.impl.model.GenericItemPreferenceArray.<init>( > GenericItemPreferenceArray.java:49) > > at org.apache.mahout.cf.taste.impl.model.GenericItemPreferenceArray.<init>( > GenericItemPreferenceArray.java:56) > > at > org.apache.mahout.cf.taste.impl.model.jdbc.AbstractJDBCDataModel.getPreferencesForItem( > AbstractJDBCDataModel.java:441) > > at > org.apache.mahout.cf.taste.impl.recommender.GenericItemBasedRecommender.doMostSimilarItems( > GenericItemBasedRecommender.java:169) > > at > org.apache.mahout.cf.taste.impl.recommender.GenericItemBasedRecommender.mostSimilarItems( > GenericItemBasedRecommender.java:128) > > at > org.apache.mahout.cf.taste.impl.recommender.GenericItemBasedRecommender.mostSimilarItems( > GenericItemBasedRecommender.java:121) > > at net.gamestreamer.recommendation.SimilarItemsFinder.find( > SimilarItemsFinder.java:18) > > at > net.gamestreamer.recommendation.test.RecommenderTest.testSimilarItemsFinder( > RecommenderTest.java:45) > > at net.gamestreamer.recommendation.test.RecommenderTest.main( > RecommenderTest.java:85) > > ========= > > When create a preference data for the > item,GenericItemBasedRecommender.mostSimilarItems() > works well. > > > On Sun, Sep 26, 2010 at 9:49 PM, Sean Owen <[email protected]> wrote: > >> GenericItemBasedRecommender.mostSimilarItems() does not care. It just >> uses your ItemSimilarity to do its work. >> You'd have to be more specific to get more feedback. Are you sure your >> ItemSimilarity is working, not returning NaN? >> >> On Sun, Sep 26, 2010 at 2:40 PM, Sam Yang <[email protected]> wrote: >> > I have custom implementation of ItemSimilarity.Does >> > GenericItemBasedRecommender.mostSimilarItems() >> > need preference data? >> > I new GenericItemBasedRecommender with the preference data model and >> > implementation >> > of ItemSimilarity,but seems mostSimilarItems() return no results. >> > > > > -- > I'm samsam. > -- I'm samsam.
