code: def _map_to_memory(self, stride=1):
          r
          self._mapping_to_mem_active = True
          try:
              self._Y = self.get_output(stride=stride)
              from pyemma.coordinates.data import DataInMemory
              self._Y_source = DataInMemory(self._Y)
          finally:
              self._mapping_to_mem_active = False
  
          self._in_memory = True
docs: r"""Maps results to memory. Will be stored in attribute :attr:`_Y`.