Spatial Pooler

See the CLA white paper for information on the spatial pooler.

Differences Between White Paper and Implementation

Concepts

Orphan Columns

Input Border

For vision problems, the columns are laid out regularly in a 2D grid and each column as a square radius of inputs that it is connected to. To avoid the edge and corner columns from having many fewer connected input bits, you can specify an input border that is excluded from the image when laying out the columns.

Shared Inputs

There was an option added to reduce the amount that a column's connection to an input bit is incremented if the input bit is shared with other active columns.

Cloning

High Tier (VIP) Columns

History

When	What
???	Spatial Pooler Memorization (aka "high tier") was added to increase learning speed. TODO: describe this
???	Reconstruction
???	Cloning
???	Option to increment shared active input bits less than non-shared
Early	Orphan columns added
Early	Input border added
Early	Topology added for vision