Detect a single inflection point of the given.

Question

评论： Alejandro Fernández 2020-6-25

Hi everyone, I was wondering if someone could help me a little to find the tipping point of that data series automatically, as data can change.

x = [15	14 13 12 11 10 9 8 7 6 5 4 3 2 1];
y = [0 1 0 1 0 0 22 49 201 255 255 255 255 255 255];

The data represented are those shown below

df1 = gradient(y,x)
df2 = gradient(df1,x)
figure
plot(x,df2,'-o','LineWidth',2)
hold on
yline(0);

But now i don't know how to decide which is de correct inflex point of these data.

I have looked in [1], [2], [3], [4], but i couldn't solve my problem.

Thank you for all.

Answer 1

Gaurav Garg 2020-6-23

Hi,

You can take use of Symbolic Math Toolbox and functions inside it to find the inflection point for your problem.

Ok thanks