Parallel Universes - NG Construct & View node bug

KNIME Extensions
#1

Hi,

I have been using the Parallel Universes/Neighbourgram nodes alot recently, they are great.

However, I do find that the "NG Construct & View" node frequently consumes a vast amount of memory when the number of neighbours are set high, and the dataset is around 1500 rows.

This in the end results in KNIME freezing permanently, and therefore KNIME needs to be terminated with the Windows "End Task" protocol.

Is there possibly some memory leaks in this node ?

Additionally, is it possible to make the "Class" setting in the node optional, as sometimes I only have one class and it means using a Rule Engine node to create a string column for no other purpose than to get the node to run.

These are great nodes for comparing items within a dataset, very powerful indeed.

Thanks,

Simon.

#2

Hi Simon,

The neighbor count is a crucial parameter (in terms of memory consumption). If you increment this value by one, each of the neighborgram holds one additional reference. So I don't think it's a memory leak but really only a characteristic of the method.

I did a test run with 1800 rows and 1800 neighbors (so each neighborgram contains the full neighborhood) and the memory consumption is at 500MB, which seems fair?!

That these errors are not caught and handled is a different story, though. I open a bug report.

Bernd