Okay thanks for the advice, i think i understand that.
Just one problem, i'm using a machine learning function.
And that wants data in a numpy array format like this;
(2D numpy array i think)
But the lines in backtrader are working different :
[1000 2000 3000 4000]
(1D array i think)
So i wonder if there is a way to convert this too a numpy array on which the algorithm is working.