Hi, I'm trying to run the ALS algorithm. However, I get the following error:
Exception in thread "pool-1-thread-3" org.apache.mahout.math.IndexException: Index -691877539 is outside allowable range of [0,2147483647) at org.apache.mahout.math.AbstractVector.set(AbstractVector.java:395) at org.apache.mahout.cf.taste.impl.recommender.svd.ALSWRFactorizer.sparseUserRatingVector(ALSWRFactorizer.java:305) At line 305 in ALSWRFactorizer.java, there is the following code ratings.set((int) preference.getItemID(), preference.getValue()); My suspicion is that the error results from the casting to int in the above line. Item IDs in mahout are long, so if you cast a long (which does not fit into an int) then you will get negative numbers and hence the error. However, this explanation also seems to me implausible since I don't think such an error exists in Mahout code. Any help will be appreciated. Thanks
