unexpected behaviour when plotting IX_dataset_1D in hisogram or distribution modes

[abuts]

if one defines defines IX_dataset_1D as histogram:

   en_bins = [cut_en-half_dE,cut_en(end)+half_dE];
   ax_x = IX_axis('Energy Transfer','meV');
   ax_s = IX_axis('Scattering amplitude','mbarn/(Sr*fmu)');
   S_eff = IX_dataset_1d(en_bins,Seff,Seff_err);
   S_eff.x_axis = ax_x;
   S_eff.s_axis = ax_s;    

when numel(en_bins) = numel(Seff)+1; plot(IX_dataset_1D) still shows Y-axis units as mbarn/(Sr*fmu)/meV, while it is histogram and these units should be provided as mbarn/(Sr*fmu).
/meV should be plotted when numel(en_bins) = numel(Seff) only.