# Interpolate Curve - Managing Lists correctly

Hello Guys this is my first thread, so if did something wrong by mistake, let me know!

for this University Project we started developing Football-stadiums.
This is what I want it to be in the end.

My Logic is to create three “Circles” ( marked in RED C1-C3 in the pic below) and divide them into a several amount of points. The list with the points have to be shifted in a amount of X to get the “Curve” and not a just a straight Line between the points.

so in the end I got this :

Im sure the mistake starts on managing the lists. so I tried to creat a single Interpolation at first, bevor applying it to all the other points. I took for all List with Points a List item at Position 0. As u can see here:

If u have an idea what I am missing, id be very thankfull for letting me know!

Kind regards from Hamburg!

Interpolation issues.gh (7.9 KB)

Hi,

The error message “Insufficient interpolation points” means you have a list of only one point. But why this would happen, as you plugged three distinct wires in the same input ?..

As discussed here, this is a tree structure problem, your items are in different branches and therefore not considered as a single list with three elements. I STRONGLY recommand using `Merge` component to anticipate - and correct with Simplify or Flatten - these problems.

In order to repeat this process on all your curves, you need to regroup all your points by lists of 3 elements, which means a tree with several branches, which means : graft.

Interpolation issues.gh (12.9 KB)

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Hello!

Thank a lot for solving this one for me! I will click around a little and see what the simplify and flatten does to the lists. It looks right but i need to practice a bit to get used to it.

Have a nice day

Or best of all,Suirify.

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