Python column segment walk

src/nupic/research/connections.py

@@ -19,7 +19,7 @@
 # http://numenta.org/licenses/
 # ----------------------------------------------------------------------
 
-from collections import defaultdict, namedtuple
+from collections import defaultdict
 
 
 
@@ -74,6 +74,19 @@ def __init__(self,
     self._nextSynapseIdx = 0
 
 
+  def segmentCmp(self, a, b):
+    """
+    A simple comparison function for segments to sort them
+    by the cell they are on.
+
+    @param a (int) segment 1
+    @param b (int) segment 2
+
+    @return (int) comparison integer between the two cells
+    """
+    return self._segments[a] - self._segments[b]
+
+
   def cellForSegment(self, segment):
     """
     Returns the cell that a segment belongs to.
@@ -85,6 +98,18 @@ def cellForSegment(self, segment):
     return self._segments[segment]
 
 
+  def columnForSegment(self, segment, cellsPerColumn):
+    """
+    Returns the column that a segment's presynapticCell belongs to
+
+    @param segment        (int) Segment index
+    @param cellsPerColumn (int) Number of cells in a column in the tm
+
+    @return (int)
+    """
+    return self._segments[segment] / cellsPerColumn
+
+
   def segmentsForCell(self, cell):
     """
     Returns the segments that belong to a cell.
@@ -109,7 +134,6 @@ def dataForSynapse(self, synapse):
 
     @return (SynapseData) Synapse data
     """
-    self._validateSynapse(synapse)
 
     return self._synapses[synapse]
 
@@ -192,7 +216,6 @@ def createSynapse(self, segment, presynapticCell, permanence):
     @return (int) Synapse index
     """
     self._validateSegment(segment)
-    self._validatePermanence(permanence)
 
     # Add data
     synapse = self._nextSynapseIdx
@@ -231,7 +254,6 @@ def updateSynapsePermanence(self, synapse, permanence):
     @param synapse    (int)   Synapse index
     @param permanence (float) New permanence
     """
-    self._validatePermanence(permanence)
 
     data = self._synapses[synapse]
     newData = SynapseData(data.segment,
@@ -243,6 +265,52 @@ def updateSynapsePermanence(self, synapse, permanence):
     self._synapsesForPresynapticCell[newData.presynapticCell][synapse] = newData
 
 
+  def computeActivity(self, activeInput, activePermanenceThreshold,
+                      activeSynapseThreshold, matchingPermananceThreshold,
+                      matchingSynapseThreshold):
+    """
+    Computes active and matching segments given the current active input.
+
+    @param activeInput                 (set)   currently active cells
+    @param activePermanenceThreshold   (float) permanence threshold for a synapse to be considered active
+    @param activeSynapseThreshold      (int)   number of synapses needed for a segment to be considered active
+    @param matchingPermananceThreshold (float) permanence threshold for a synapse to be considered matching
+    @param matchingSynapseThreshold    (int)   number of synapses needed for a segment to be considered matching
+
+    @return (tuple) Contains:
+                      `activeSegments`         (list),
+                      `matchingSegments`        (list),
+
+    Notes:
+      activeSegments and matchingSegments are sorted by the cell they are on.
+    """
+
+    numActiveSynapsesForSegment = [0] * self._nextSegmentIdx
+    numMatchingSynapsesForSegment = [0] * self._nextSegmentIdx
+
+    for cell in activeInput:
+      for synapseData in self.synapsesForPresynapticCell(cell).values():
+        segment = synapseData.segment
+        permanence = synapseData.permanence
+        if permanence >= matchingPermananceThreshold:
+          numMatchingSynapsesForSegment[segment] += 1
+          if synapseData.permanence >= activePermanenceThreshold:
+            numActiveSynapsesForSegment[segment] += 1
+
+    activeSegments = []
+    matchingSegments = []
+    for i in xrange(self._nextSegmentIdx):
+      if numActiveSynapsesForSegment[i] >= activeSynapseThreshold:
+        activeSegments.append(i)
+
+    for i in xrange(self._nextSegmentIdx):
+      if numMatchingSynapsesForSegment[i] >= matchingSynapseThreshold:
+        matchingSegments.append(i)
+
+    return (sorted(activeSegments, cmp=self.segmentCmp),
+            sorted(matchingSegments, cmp=self.segmentCmp))
+
+
   def numSegments(self):
     """
     Returns the number of segments.
@@ -281,6 +349,7 @@ def write(self, proto):
           protoSynapse.permanence = synapseData.permanence
 
 
+
   @classmethod
   def read(cls, proto):
     """
@@ -304,9 +373,9 @@ def read(cls, proto):
 
         for k in xrange(len(protoSynapses)):
           protoSynapse = protoSynapses[k]
-          synapse = connections.createSynapse(segment,
-                                              int(protoSynapse.presynapticCell),
-                                              protoSynapse.permanence)
+          connections.createSynapse(segment,
+                                    int(protoSynapse.presynapticCell),
+                                    protoSynapse.permanence)
 
     return connections
 
@@ -331,16 +400,16 @@ def __eq__(self, other):
       otherSegmentSet = set()
       for segment in other.segmentsForCell(cell):
         otherSynapseSet = other._synapseSetForSynapses(
-                       other.synapsesForSegment(segment))
+          other.synapsesForSegment(segment))
         otherSegmentSet.add(frozenset(otherSynapseSet))
 
       if segmentSet != otherSegmentSet: return False
 
       synapseSet = self._synapseSetForSynapses(
-                     self.synapsesForPresynapticCell(cell))
+        self.synapsesForPresynapticCell(cell))
 
       otherSynapseSet = other._synapseSetForSynapses(
-                    other.synapsesForPresynapticCell(cell))
+        other.synapsesForPresynapticCell(cell))
 
       if synapseSet != otherSynapseSet: return False
 
@@ -373,7 +442,7 @@ def _synapseSetForSynapses(self, synapses):
     for synapse in synapses:
       synapseData = self.dataForSynapse(synapse)
       synapseSet.add((synapseData.presynapticCell,
-                     round(synapseData.permanence, 7)))
+                      round(synapseData.permanence, 7)))
 
     return synapseSet
 
@@ -396,24 +465,3 @@ def _validateSegment(self, segment):
     """
     if not segment in self._segments:
       raise IndexError("Invalid segment")
-
-
-  def _validateSynapse(self, synapse):
-    """
-    Raises an error if synapse index is invalid.
-
-    @param synapse (int) Synapse index
-    """
-    if not synapse in self._synapses:
-      raise IndexError("Invalid synapse")
-
-
-  @staticmethod
-  def _validatePermanence(permanence):
-    """
-    Raises an error if permanence is invalid.
-
-    @param permanence (float) Permanence
-    """
-    if permanence < 0 or permanence > 1:
-      raise ValueError("Invalid permanence")