What would I see from "position" using serial.println(position)?
I really think that you'd learn more by just trying it.
That snippet doesn't tell US anything about the input values (in pinval_N, so we can't guess what the output would be. YOU have access to the values, so you should be able to define a relationship between the input and the output.
Of course, you could also learn (by reading the reference page) what << does, and KNOW what the relationship between the input and the output is.