SpatialPooler: inhibitColumnsGlobal() does unneeded reverse sort on returned list

[cogmission]

I think this is a hold-over from before the stimulusThreshold enforcement, that never got reconsidered?

The list returned is the list of active columns (in sparse form), and is used in 2 downstream methods:

1. _adaptSynapses
2. _updateDutyCycles

...in the first method, the sparse list of columns is only used as indexes to iterate over; and in the second, the sparse list is used to create a dense list whose indexes indicated by the sparse list are made 1's.

return sortedWinnerIndices[start:][::-1]

Argument: I'm thinking there is no reason to sort the list in reverse order? Even if there is some "magical" underlying C++ method which does it quickly, it's still a useless operation and results in cognitive dissonance for the reader?

[rhyolight]

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