How to integrate this function correctly?

Hey,

this seems like a rather simpel problem but I don't seem to get it right.

I'm given the following integral: = and the following dataset:

time = [0 1 2 3 4 5 6 7 8 9 10 12 14]';
E = [0 0.0199867 0.0999334 0.1598934 0.1998668 0.1598934 0.1199201 0.0799467 0.05996 0.0439707 0.02998 0.011992 0]';  

Next I used trapz to solve with a result of = 32.2409. However, I know that the correct answer should be ~6.1. What am I doing wrong?

y_sigma = time.^2 .* E;
sigma = trapz(time,y_sigma)

Thanks in advance,

Danny

Answer 1

[Fabio Freschi]

I don't see nothing wrong in the result you get. The result is correct also "'by looking" at time-y_sigma graph. My guesses:

• Are your data correct?
• you got sigma^2, but maybe you should write

sigma = sqrt(trapz(time,y_sigma)) % 5.7130