looking how basic functions are made

Hi
I'm not a programmer so I'm sorry if this question is too banal.
I started to fiddle with Zorro.
I'm in workshop 4 and I would like to see how peaks and valleys are made, because I don't understand them and I don't understand what's happening.
So I went into root and Source folder: I'm looking at indicators.c and zorro.h; peak0 is called but I don't find where it is.
May you help me?
Thanks

For simple functions, such as peak/valley, you can find the algorithm in the manual