code: def encodeIntoArray(self, input, output):
      
  
      if input == SENTINEL_VALUE_FOR_MISSING_DATA:
        output[0:] = 0
      else:
        if not isinstance(input, datetime.datetime):
          raise ValueError("Input is type %s, expected datetime. Value: %s" % (
              type(input), str(input)))
  
        # Get the scalar values for each sub-field
        scalars = self.getScalars(input)
        # Encoder each sub-field
        for i in xrange(len(self.encoders)):
          (name, encoder, offset) = self.encoders[i]
          encoder.encodeIntoArray(scalars[i], output[offset:])
docs: See method description in base.py