///<summary>
/// This function reinforces each segment in this Cell's SegmentUpdate.
/// </summary>
/// <remarks>
/// Using the segmentUpdate, the following changes are
/// performed. If positiveReinforcement is true then synapses on the active
/// list get their permanence counts incremented by permanenceInc. All other
/// synapses get their permanence counts decremented by permanenceDec. If
/// positiveReinforcement is false, then synapses on the active list get
/// their permanence counts decremented by permanenceDec. After this step,
/// any synapses in segmentUpdate that do yet exist get added with a permanence
/// count of initialPerm. These new synapses are randomly chosen from the
/// set of all cells that have learnState output = 1 at time step t.
///</remarks>
internal void ApplySegmentUpdates(bool positiveReinforcement, int latestCreationStep = -1)
{
// This loop iterates through a list of SegmentUpdate's and reinforces each segment.
foreach (var segmentUpdate in this.SegmentUpdates)
{
DistalSegment distalSegment = segmentUpdate.DistalSegment;
if (distalSegment != null)
{
if (positiveReinforcement)
{
distalSegment.UpdatePermanences(segmentUpdate.ActiveDistalSynapses);
}
else
{
distalSegment.DecreasePermanences(segmentUpdate.ActiveDistalSynapses);
}
}
// Add new synapses (and new segment if necessary)
if (segmentUpdate.AddNewSynapses && positiveReinforcement)
{
if (distalSegment == null)
{
// Only add new segment if end cells to connect are available
if (segmentUpdate.CellsToConnect.Count > 0)
{
distalSegment = segmentUpdate.CreateDistalSegment();
}
}
else if (segmentUpdate.CellsToConnect.Count > 0)
{
// Add new synapses to existing segment
segmentUpdate.CreateDistalSynapses();
}
}
}
// Delete segment update instances after they are applied
this.SegmentUpdates.Clear();
}
