  n_start: days to be removed after start of recession
   eps: allowed increase in flow during recession period, default = 0
       (note that large eps values can lead to problematic recession
       selection)
   start_of_recession: define start of recession when baseflow filter
       rejoins the curve &quot;baseflow&quot; or after peak &quot;peak&quot;
   filter_par: smoothing parameter of Lyne-Hollick filter to determine
      start of recession (higher = later recession start), default = 0.925
   plot