What you would need to do is debug org.apache.mahout.cf.taste.example.grouplens.GroupLensDataModel, which is under examples/src. The skeleton web application that gets created as part of this deployment target will take care of initializing the Recommender, which should init this in turn. The key part is where it delegates to the FileDataModel constructor, I think (line 53); something is not going right around there.
One idea comes to mind: look in your machine's temp directory for files starting with 'ratings' or 'movies' and delete them if they exist and try again. I don't mind sifting through a lot of log output, but the part generated by this code should be relatively small... should be messages about initializing FileDataModel somewhere in there, with clues perhaps. On Mon, Jun 1, 2009 at 5:06 PM, Jack Tanner <[email protected]> wrote: > > Right. I'm happy to do debugging and/or send log files... But there's a ton > printed to stdout. So, with respect to the 11 steps at > http://lucene.apache.org/mahout/taste.html#demo , which step produces the > DataModel? And where in the file system is it supposed to live? > > ---------------------------------------- >> Date: Mon, 1 Jun 2009 16:43:43 +0100 >> Subject: Re: RE: taste-web example booboo >> From: [email protected] >> To: [email protected] >> >> Yes that is the same error, but more descriptive now. >> >> There should be log output from the code on stdout - I wonder what that >> shows? Turning the output level down to FINE would show even more. >> >> You can call methods on DataModel to check its state and print the result. I >> am pretty sure you will find it loaded nothing for some reason. The file is >> there, but... hmm. I am having trouble guessing how it succeeds but then has >> no data. Some more log output - or if you care to, some debugging - is the >> next step. >> >> Sean >> >> On Jun 1, 2009 4:32 PM, "Jack Tanner" wrote: >> >> >> This still doesn't work for me off trunk. :( The new error is "dataModel has >> no items". When is the data model supposed to be generated? How can I check >> whether it has items or not? >> >> This is on Fedora 10, maven 2.1.0. >> HTTP ERROR: 500dataModel has no items >> RequestURI=/mahout-taste-webapp/RecommenderServletCaused >> by:java.lang.IllegalArgumentException: dataModel has no items >> at >> org.apache.mahout.cf.taste.impl.recommender.slopeone.MemoryDiffStorage.(MemoryDiffStorage.java:101) >> >> at >> org.apache.mahout.cf.taste.impl.recommender.slopeone.SlopeOneRecommender.(SlopeOneRecommender.ja... >> at >> org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:365) >> at >> org.mortbay.jetty.security.ConstraintsSecurityHandler.handle(ConstraintsSecurityHandler.java:220) >> >> at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181) >> at >> org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:822) >> at >> org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:305) >> at >> org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:229) >> at >> org.mortbay.jetty.handler.HandlerCollection.handle(HandlerCollection.java:113) >> >> at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) >> at org.mortbay.jetty.S... >> at >> org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:550) >> at >> org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:876) >> at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:535) >> at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:209) >> at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:407) >> at >> org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:421) >> >> at >> org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:520) >> >> Powered by Jetty:// >> >> ---------------------------------------- >>> Date: Fri, 29 May 2009 23:03:06 +0100 >> >>> Subject: Re: taste-web example booboo> From: [email protected]> To: >> [email protected]... >> >>> Oh sorry, missed that bit. Well... whatever it is, seems to be fixed.> I >> do know there were some ... >> >>> On Fri, May 29, 2009 at 10:41 PM, Jack Tanner wrote:>>>> Sean,>>>> I >> did not use the latest c... >> _________________________________________________________________ >> Windows Live™: Keep your life in sync. >> http://windowslive.com/explore?ocid=TXT_TAGLM_BR_life_in_synch_052009 > > _________________________________________________________________ > Hotmail® has a new way to see what's up with your friends. > http://windowslive.com/Tutorial/Hotmail/WhatsNew?ocid=TXT_TAGLM_WL_HM_Tutorial_WhatsNew1_052009
