code: def printActiveIndices(self, state, andValues=False):
      
      (cols, cellIdxs) = state.nonzero()
  
      if len(cols) == 0:
        print "NONE"
        return
  
      prevCol = -1
      for (col,cellIdx) in zip(cols, cellIdxs):
        if col != prevCol:
          if prevCol != -1:
            print "] ",
          print "Col %d: [" % (col),
          prevCol = col
  
        if andValues:
          print "%d: %s," % (cellIdx, state[col,cellIdx]),
        else:
          print "%d," % (cellIdx),
      print "]"
docs: Print the list of [column, cellIdx] indices for each of the active
      cells in state.