I’ve created various models where after the model has run for some time the classifier confidence value starts returning NaN.
As a sanity check, I’ve gone back to the standard hotgym example (http://nupic.docs.numenta.org/stable/quick-start/network.html) and found that it too suffers from this problem.
For data, I am using the rec-center-hourly.csv file (https://github.com/numenta/nupic/tree/master/examples/opf/clients/hotgym/prediction/one_gym), but I am replicating/extending the data to have 30000 time steps (rather than the default 4394 times points).
Nothing else is being changed from the default hotgym code/model.
Specifically, at about the 19000th data point, the 5-step ahead confidence starts returning NaN.
What would be causing this?
Is it a bug?
Is there any way to guarantee that the classifier will not return a NaN?