code: def save_data(data, suffix='', dirname=None):
      
      if type(data) == list:
          data = np.array(data).T
  
      name = create_graph_name(suffix, dirname) + '.txt'
      np.savetxt(name, data)
docs: Save a dataset using caller's name.
  
      :param data: a list or numpy array containing the data
      :param suffix: optional suffix to add to name
      :param dirname: optional directory name