code: def _calculateOverlap(self, inputVector):
      
      overlaps = numpy.zeros(self._numColumns, dtype=realDType)
      self._connectedSynapses.rightVecSumAtNZ_fast(inputVector.astype(realDType),
                                                   overlaps)
      return overlaps
docs: This function determines each column's overlap with the current input
      vector. The overlap of a column is the number of synapses for that column
      that are connected (permanence value is greater than '_synPermConnected')
      to input bits which are turned on. The implementation takes advantage of
      the SparseBinaryMatrix class to perform this calculation efficiently.
  
      Parameters:
      ----------------------------
      :param inputVector: a numpy array of 0's and 1's that comprises the input to
                      the spatial pooler.