Area under a plot (Integral)

Hi Everyone,

i have a plot which looks like this:<<http://www.tiikoni.com/tis/view/?id=f7a4a17>>. I'm trying to figure out the best way to find the area under the curve i.e. the integral. Two solutions come to mind, the simpsons rule or the trapz method.

totalpowerconsumed = trapz(times, power); % gives me a strange answer, it says that the total power consumed it 0.500 exactly, which i find unlikely. The simpsons rule is another method, but im not sure how to do it, it seems like i have to find a function which approximates this plot.

which method would you suggest? and if you pick the simpsons one, can you please help me set it up a bit?

Thank you!

Answer 1

[Ilham Hardy]

I think you should use

cumtrapz

instead of

   trapz

Answer 2

[Sean de Wolski]

Why don't you trust the output from trapz()? It looks at least feasible to me.

To test it, create some fake data, or add some data to the end of it with a known area of 1 or similar...