code: def bs_plot_data(self):
  
          
          distance = []
          frequency = []
  
          ticks = self.get_ticks()
  
          for b in self._bs.branches:
  
              frequency.append([])
              distance.append([self._bs.distance[j]
                               for j in range(b['start_index'],
                                              b['end_index'] + 1)])
  
              for i in range(self._nb_bands):
                  frequency[-1].append(
                      [self._bs.bands[i][j]
                       for j in range(b['start_index'], b['end_index'] + 1)])
  
          return {'ticks': ticks, 'distances': distance, 'frequency': frequency,
                  'lattice': self._bs.lattice_rec.as_dict()}
docs: Get the data nicely formatted for a plot
  
          Returns:
              A dict of the following format:
              ticks: A dict with the 'distances' at which there is a qpoint (the
              x axis) and the labels (None if no label)
              frequencies: A list (one element for each branch) of frequencies for
              each qpoint: [branch][qpoint][mode]. The data is
              stored by branch to facilitate the plotting
              lattice: The reciprocal lattice.