It would help to have the code, or at least a file thtat I can get the information from.
Lacking that, a bit of creativity is in order —
x = linspace(-50, 175, 500).'; % Assume Column Vectors
y = -0.45 - 2*exp(-(x-107.5).^2/4)+(-0.0005*x);
Lv = (x > 100) & (x < 115);
Lvn = find(Lv);
ytop = interp1(x([Lvn(1) Lvn(end)]), y([Lvn(1) Lvn(end)]), x(Lvn));
figure
plot(x, y)
hold on
patch([x(Lv); flip(x(Lv))], [y(Lv); ytop], 'b', 'FaceAlpha',0.5, 'EdgeColor','none')
hold off
grid
xlim([min(x) max(x)])
It is a bit difficult to understand what you want shaded. This is my best guess.
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