Hi, thank you for your response.
I removed the multiple items and know I don't get an exception. >> Is it neccessary to use itemsets with equal length? >No - fixed size itemsets are not required. >> Is it possible to use itemsets with duplicates in mahout FPGrowth? >Not reliably. This crash looks like it caused by having more items in >one particular itemset than in the set of items with at least >min-support. Perhaps more simply, if you have three items that meet >your support cutoff, and you encounter an itemset like: "item1 item1 >tem2 item3", this will happen. >It won't crash here in every case where you have multiples of items; for >example "item1 item1 item2" will not crash. I'm not sure precisely how >that will be treated down the line, but my assumption is that your >results would be subtly wrong somehow. >It would be pretty straightforward to fix this, and either tolerate >multiples gracefully by collapsing "baskets" into itemsets or bailing >out with an error. I think we'd just need to fix TransactionIterator >and also check the initial counting pass (ParallelCountingDriver and its >non-MR counterpart). >-tom regards Jens
