I am not certain what you want to do with these data. I have no idea what ‘NDIV’ refers to.
This creates patch objects beginning with the date before each non-NaN value in ‘NDIV’ and extending to the next date in the series. I am guessing as to what you want, so you may need to change this to get the result you want, however it should get you started.
Try this —
T1 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/1321105/Whole_periodNDVI_smo.xlsx', 'VariableNamingRule','preserve')
[G,ID] = findgroups(year(T1.('Time series')));
for k = 1:numel(ID)
Yrs{k,:} = T1(k==G,:);
end
figure
for k = 1:numel(Yrs)
% Yrs{k}
subplot(2,1,k)
v = find(~isnan(Yrs{k}.NDIV));
for k1 = 1:numel(v)
vidx = v(k1)+[-1;1];
xp = [Yrs{k}(vidx,:).('Time series'); flip(Yrs{k}(vidx,:).('Time series'))];
yp = reshape([ylim;ylim], [], 1);
hph = patch(xp, yp, 'r', 'DisplayName','NDIV', 'EdgeColor','r');
end
hold on
hpp = plot(Yrs{k}.('Time series'), Yrs{k}.Smoothed, 'DisplayName','Smoothed');
hold off
legend([hph(1),hpp], 'Location','bestoutside')
end
.
