Note that this reference documentation is identical to the help that is displayed in MATLAB when you type “help ft_preproc_slidingrange”.

  FT_PREPROC_SLIDINGRANGE computes the range of the data in a sliding time
  window of the width specified. Width should be an odd number (since the
  window needs to be centered on an individual sample).
  Use as
    y = ft_preproc_slidingrange(dat, width, ...)
  Optional key-value pair arguments are:
    'normalize', whether to normalize the range of the data with the square
                 root of the window size