hello
this is my suggestion, hope it helps
clc
clearvars
fileDir = pwd;
sheet = 2; % data must be retrieved from sheet #2
S = dir(fullfile(fileDir,'output*.xlsx')); % get list of data files in directory
S = natsortfiles(S); % sort file names into natural order (what matlab does not) , see FEX :
%(https://fr.mathworks.com/matlabcentral/fileexchange/47434-natural-order-filename-sort)
legstr = [{'img1 F'};{'img2 F'};{'img3 F'};{'img4 M'};{'img5 M'};{'img6 M'};{'img8 F'};{'img9 M'};{'img10 F'}];
for k = 1:length(S)
data = xlsread(fullfile(fileDir, S(k).name),sheet); % or use a structure (S(k).data ) to store the full data structure
% data array must be splitted in two (fig 1 and fig 2 ) by checking the
% NaN position
ind_nan = find(isnan(data(1,:)));
cols = ind_nan-1;
x1 = data(1,1:cols);
y1 = data(2:end,1:cols);
x2 = data(1,end-cols+1:end);
y2 = data(2:end,end-cols+1:end);
% plot
filename_fig = S(k).name;
ind = findstr(filename_fig,'.');
filename_fig = filename_fig(1:ind-1);
% figure(k); % will create k figures
figure(1); % will create 1 figure only (updated after each new data) => faster batch processing
sg = sgtitle(filename_fig);
sg.FontSize = 20;
sg.FontWeight = 'bold';
subplot(121),plot(x1*100,y1);
xlabel('Percentage');
ylabel('f0 (Hz)');
xtickformat('percentage');
subplot(122),plot(x2*100,y2);
ll= legend(legstr,'Location','South','Orientation','horizontal');
set(ll,'Position',[0.2119 0.015 0.6332 0.0323])
xlabel('Percentage');
ylabel('f0 (Hz)');
xtickformat('percentage')
print(filename_fig, '-dpng')
end
