# Cross Reference in Grasshopper

Hi gang,

Can someone explain to me why cross reference behaves the way it does here
Ive taken two list of numbers as cross referenced them to provide me with a set of numbers to perform paraboloid function.

Looking at this more closely, The input, and then output operations of Cross Reference A & B are different.
Where A ( I assume ) registers the List of Input B and repeats itself according to that number.

B, however seems to have no relationship with A ? Where it just multiplies internally with the list from input B.

My question and query is just to understand the logic of cross reference when dealing with numbers, and we can

Kindest,
Liam

question.gh (13.6 KB)

you are correct, I think the easiest way to see it is that list A is repeated “length of list B” times, and each item in B is repeated “length of list A” times

question (1)_Re.gh (14.6 KB)

as if you were constructing a point with those values (A=x, B=y) and y was grafted:

easier to see if you polyline the final points:

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