if i have a plot, how do i have find the derivative of the plot?

for example i have plot(x,y) how do i have find the derivative of it and then find the zeros in that derivative plot?

Answer 1

[John Petersen]

Do you have a preferred method of taking the derivative? There are many. A simple one (that does not work well for noisy data) is

dy = diff(y)./diff(x);

To find zeros, you could search for where dy changes sign.