Area of A PV Otto Cycle

So I'm working with a set of engine data and I'm trying to find the IMEPn, IMEPg, and PMEP of the graph attached. I was able to get the plot, but I'm unsure of how to get the area of each individual section i.e the "boomerang" and the little slivver of enclosed area below to calculate the values I need. Any advice on how to go about calculating these areas separately? I've tried using trapz and cumtrapz, but I'm not getting the correct area. If it's needed I can attached the code for those that want to run it themselves otherwise I'll just post the graph for a visual. As a reference, if you do use the code, the values should be IMEPn=4.08 bar, IMEPg=4.6 bar, PMEP=-0.51 bar.

All help is appreciated!

[KSSV]

You have two regions in that.....have a look on polyarea. If not attach your data.

[Hope Wilson]

I'll check that out and get back to you!

[Hope Wilson]

That worked after some finicking with the X and Y values. Thank you so much!