class_docstr: Online Updating Ensemble of forecasters.
  
  Parameters
  ----------
  ensemble_algorithm : ensemble algorithm
  forecasters : list of (str, estimator) tuples
  n_jobs : int or None, optional (default=None)
      The number of jobs to run in parallel for fit. None means 1 unless
      in a joblib.parallel_backend context.
      -1 means using all processors.
class_docstr_tok: ["Online","Updating","Ensemble","of","forecasters",".","Parameters","--","--","--","--","--","ensemble_algorithm",":","ensemble","algorithm","forecasters",":","list","of","(","str",",","estimator",")","tuples","n_jobs",":","int","or","None",",","optional","(","default=None",")","The","number","of","jobs","to","run","in","parallel","for","fit",".","None","means","1","unless","in","a","joblib.parallel_backend","context",".","-1","means","using","all","processors","."]
docstr: Update fitted parameters and performs a new ensemble fit.
  
  Parameters
  ----------
  y : pd.Series
  X : pd.DataFrame
  update_params : bool, optional (default=False)
  
  Returns
  -------
  self : an instance of self
docstr_tok: ["Update","fitted","parameters","and","performs","a","new","ensemble","fit",".","Parameters","--","--","--","--","--","y",":","pd.Series","X",":","pd.DataFrame","update_params",":","bool",",","optional","(","default=False",")","Returns","--","--","--","-","self",":","an","instance","of","self"]
code: def _update(self, y, X=None, update_params=False):
      """Update fitted parameters and performs a new ensemble fit.
  
      Parameters
      ----------
      y : pd.Series
      X : pd.DataFrame
      update_params : bool, optional (default=False)
  
      Returns
      -------
      self : an instance of self
      """
      if len(y) >= 1 and self.ensemble_algorithm is not None:
          self._fit_ensemble(y, X)
  
      for forecaster in self.forecasters_:
          forecaster.update(y, X, update_params=update_params)
  
      return self
  
file_path: sktime/sktime/forecasting/online_learning/_online_ensemble.py
imports: import numpy
  import pandas
  from sktime.forecasting.compose._ensemble import EnsembleForecaster
label_desc: Use image node_id 4 for calling the OnlineEnsembleForecaster obj's underlying member method code with example usage: obj._update(y, X, update_params) and returns: self