Shade or fill area between several lines in same plot (probability function was used for plotting)

I am trying to shade or fill area between lines in same plot. Plot and data is attatched.

Answer 1

[Voss]

One way is to use patch

load('Florea_2.mat');

% annularrimx = xlsread('C:\Users\almha\Desktop\Rayan\Probability.xlsx'); % I changed this, if different location, you can change it back
% 
% 
% x = annularrimx(:,1);

figure
% hold all

% store the handles to the plotted lines in variable h
h = probplot('lognormal',[sample_02.Discharge_ratio sample_04.Discharge_ratio sample_07.Discharge_ratio sample_08.Discharge_ratio sample_10.Discharge_ratio sample_13.Discharge_ratio sample_21.Discharge_ratio sample_22.Discharge_ratio sample_23.Discharge_ratio],'noref');

% area(x,sample_04, 'g')
grid on
% hold off
legend(sample_02.info,sample_04.info,sample_07.info,sample_08.info,sample_10.info,sample_13.info,sample_21.info,sample_22.info,sample_23.info)
title('{\bf Probability Plot}')
set(get(gca,'XLabel'),'String','Discharge Ratio (Q/Qmin)')

% indices of plotted lines to fill between (adjust as needed):
h_idx = [ ...
    6 9; ... % fill between Royal, KY, line and Comal, TX, line, using color of Royal, KY, line
    9 8; ... % fill between Comal, TX, line and Blue, MO, line, using color of Comal, TX, line
    8 7; ... % etc.
    7 3; ...
    3 2; ...
    2 5; ...
    5 1; ...
    1 4; ...
    ];
p = zeros(size(h_idx,1),1);
for ii = 1:size(h_idx,1)
    p(ii) = patch( ...
        [h(h_idx(ii,1)).XData h(h_idx(ii,2)).XData(end:-1:1)], ...
        [h(h_idx(ii,1)).YData h(h_idx(ii,2)).YData(end:-1:1)], ...
        h(h_idx(ii,1)).Color);
end
set(p,'EdgeColor','none','HandleVisibility','off','FaceAlpha',0.5);
set(gca(),'Children',[h(end:-1:1); p]);

[Ali alshamrani]

Thank you so much. However, how did you come up with these number for h_idx = [ ...

6 9;