How to correct the drift in the plot after cumtrapz?I have a data which has certain values and when I run the cumtrapz there is a periodic drift.Can someone help in rectifying this

How to correct the drift in the plot after cumtrapz?I have a data which has certain values and when I run the cumtrapz there is a periodic drift. k4=cumtrapz(k3); Here k3 is having values in a column and when I run the cumtrapz function it gives plot with upward drift.I want it in the same level.

[Are Mjaavatten]

If

 k4=cumtrapz(k3)

k4(i) is the value of the area under the curve defined by k3(1:i). As long as the elements of k3 are positive this area will increase as i increases. Thus the curve of k4 should indeed have an upward trend if mean(k3) > 0. If you expect otherwise, maybe cumtrapz is not what you want.

Answer 1

[Star Strider]

I don’t have ‘k3’, so I can’t comment specifically. However, remember that if you have a constant, integrating it will result in a line with an upward slope (if the constant is positive) or negative (if the constant is negative):

syms f(x) 
f(x) = 2;
V = int(f, x)

V(x) =
2*x

Q.E.D.