SP Topology is weird when input width and height are different

[vladim0105]

I’ve been experimenting with topology and the spatial pooler, but I am getting strange results. My input consists of an SDR which has 3 filled circles of active bits. I expect the spatial pooler to produce output which has a similar topology, however what I am getting instead is this:

The output matches the y-location of the input, but for some reason it has activations along the entire width of the column dimensions. It seems to be wrapping around the width. This happens even when the spatial pooler column dimensions match the input space dimensions. Setting the receptive field of each column to 1 alleviates the problem.

Is this intended behavior?

[ctrl-z-9000-times]

Ok, I think I reproduced the issue here.

Setting the spatial pooler parameter: wrapAround=False appears to fix it.

[vladim0105]

The issue persisted for me even when wrapAround was set to false, forgot to include that in the issue :/

[ctrl-z-9000-times]

Could you post your spatial pooler's parameters?
It would help in reproducing your issue.

[vladim0105]

Yes of course, I've changed them since I moved on to 1:1 aspect ratio input, but they were something like this:

    sp_args.inputDimensions = (512, 288)
    sp_args.columnDimensions = (128, 64)
    sp_args.potentialPct = 0.25
    sp_args.potentialRadius = 10
    sp_args.localAreaDensity = 0.1
    sp_args.globalInhibition = False
    sp_args.wrapAround = False
    sp_args.synPermActiveInc = 0.001
    sp_args.synPermInactiveDec = 0.00001
    sp_args.stimulusThreshold = 3
    sp_args.boostStrength = 0
    sp_args.dutyCyclePeriod = 10000000

Don't hesitate to ask if you need more info! :)

[ctrl-z-9000-times]

Sorry, I don't know when I will have the time to work on this issue.