This should do what you want —
F = openfig(websave('Group10%20heating','https://www.mathworks.com/matlabcentral/answers/uploaded_files/1171588/Group10%20heating.fig'));
Kids = F.Children;
for k = 1:numel(Kids)
yv(k,:) = Kids(k).Children.YData;
end
xv = Kids(1).Children.XData;
The ‘yv’ array are the YData vectors for each subplot, and the ‘xv’ vector is the common independent variable vector for all of them.
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