Skip to content

Latest commit

 

History

History
81 lines (71 loc) · 3.73 KB

CHANGELOG.md

File metadata and controls

81 lines (71 loc) · 3.73 KB

Change Log

Unreleased

Changed

0.0.14 - 2016-07-01

Changed

  • No more temporal pooling excitation. Instead, synapses from predicted cells excite their target cells over multiple time steps.
  • No more union pooling; activation level is constant.
  • First level layers are not treated any differently from higher layers.
    • Proximal synapses grow to any active synapses, not just stable ones.
    • Winner cells remain the same in continuing active columns unless reset; we may rely on an external timing signal to distinguish repeats.
    • Learn on winner cells only when they become active (even at first level). But might revisit this to learn auto-associatively for pattern completion.
  • Inhibition radius is now full span of receptive field size, not half of it.
  • Do not displace synapses when growing; instead wait for them to be culled.
  • Spec :spatial-pooling :local-inhibition replaces :global-inhibition? true.

Added

  • Spec parameter :stable-activation-steps
  • State key :stable-cells-buffer
  • Can create 2D regions with 3D inputs.
  • Can specify custom spatial pooling function via spec key :spatial-pooling.
  • Adjust overlap based on overlap duty cycle, to compare to NuPIC.
  • Sampling Linear Encoder
  • periodic? option to linear-encoder
  • core/segs-proximal-bit-votes
  • Spec parameter :inh-radius-scale
  • Optional instantaneous lateral synapse graph, eg for learned lateral inhibition.
  • Multimethods for customisation of algorithms, selected by spec keys :spatial-pooling and :temporal-pooling.
  • Adjust overlap by activation frequency. disable by :float-overlap-duty-ratio 0
  • Effective time steps by sufficient difference in columns :transition-similarity.

Removed

  • Spec parameters :temporal-pooling-max-exc, -fall, -amp
  • Spec parameters :activation-level-max, :stable-inbit-frac-threshold
  • State keys :engaged?, :newly-engaged?
  • temporal-pooling-cells protocol function.
  • Spec parameter :global-inhibition?

Fixed

  • coord-distance now uses Chebyshev distance to match neighbours function.
  • Local inhibition failed when inhibition-base-distance >= inh-radius.
  • Bursting defined by depolarisation; distinguishes bursting when depth=1.
  • Distal punishment cells were incorrect.

0.0.13 - 2016-01-12

Changed

  • Winner cells are not selected in layer-activate phase, only later in the layer-learn phase.
  • LayerActiveState no longer has keys :distal-learning, :proximal-learning, etc.
  • LayerOfCells now has key :learn-state which is a LayerLearnState record.
  • Abandoned the bias against cells with existing inactive segments.
  • :matching-[ff-]seg-paths now holds [seg-path exc] tuples instead of just seg-path.
  • Removed :well-matching-seg-paths and :well-matching-ff-seg-paths.
  • In LayerDistalState renamed :on-bits to :active-bits and :on-lc-bits to :learnable-bits
  • 2D and 3D topologies now index across rows first, like image pixels.

Added

  • LayerActiveState gains a key :col-active-cells, a map keyed by col id.
  • Spec parameter :apical-bias-frac
  • NoEncoder to pass in sparse distributed representations directly.

Fixed

  • Segments with connected synapses below :new-synapse-count but above :stimulus-threshold were not automatically chosen, instead falling through to partial matches (including disconnected synapses).
  • The wrong segment index was chosen for a partial match when some cells had no segments. (cell-segs was filtered)

0.0.12 - 2015-12-01

  • Before this I didn't keep a change log.