text: """
  ==============
  HF-SEF dataset
  ==============
  
  This example looks at high-frequency SEF responses.
  """
  # Author: Jussi Nurminen (jnu@iki.fi)
  #
  # License: BSD (3-clause)
  
  
  import mne
  import os
  from mne.datasets import hf_sef
  
  fname_evoked = os.path.join(hf_sef.data_path(),
                              'MEG/subject_b/hf_sef_15min-ave.fif')
  
  print(__doc__)
  
  ###############################################################################
  # Read evoked data
  evoked = mne.Evoked(fname_evoked)
  
  ###############################################################################
  # Create a highpass filtered version
  evoked_hp = evoked.copy()
  evoked_hp.filter(l_freq=300, h_freq=None, fir_design='firwin')
  
  ###############################################################################
  # Compare high-pass filtered and unfiltered data on a single channel
  ch = 'MEG0443'
  pick = evoked.ch_names.index(ch)
  edi = {'HF': evoked_hp, 'Regular': evoked}
  mne.viz.plot_compare_evokeds(edi, picks=pick)
  