How to delete a part of a curve?

I want to delete parts of this curve in order to get the regions in which a particular compound is stable. How do i delete the red and blu lines upto the shown point and the green line after the point.

Answer 1

[Yongjian Feng]

Can you find the point? If you know the point (say t1), then you can have

T1 = linspace(t1, 1500, 100);
T2 = linspace(300, t1, 100);

plot(T2, m1);
plot(T2, m3);
plot(T1, m2);

Is this what you want?