code: def get_doc_indices(self):
  		'''
  		Returns
  		-------
  		np.array
  
  		Integer document indices
  		'''
  		if self._document_category_df is None:
  			return pd.np.array([])
  		categories_d = {d: i for i, d in enumerate(self.get_categories())}
  		return self._document_category_df.category.apply(categories_d.get).valuef get_doc_indices(self):
  		'''
  		Returns
  		-------
  		np.array
  
  		Integer document indices
  		'''
  		if self._document_category_df is None:
  			return pd.np.array([])
  		categories_d = {d: i for i, d in enumerate(self.get_categories())}
  		return self._document_category_df.category.apply(categories_d.get).values
docs: Returns
  		-------
  		np.array
  
  		Integer document indices