Make "Compound" not close output path

Hello. I am making a project with sinewaves, and after I take difference with ellipse, the output result is a closed sine wave, which is not exactly what I want.

Do you know the way to alter this Compound node behavior, or somehow to remove the last point from each output path?
I attach the picture of how the sinewaves copies look prior to compound

In this case it might be better to use the delete node instead of a compound node.
Connect the wavy lines to the shape port of a delete node and connect an ellipse node to the bounding port. Keep the scope to "points" and the operation as "delete non-selected".

The problem is that wavy lines are created from a bunch of arcs and when I pass them to Delete node... well, the results are somewhat strange

I see. I did not realize you made your own wave function network. There is a wave node though that can be used to make sine waves. Anyway I took your sinewave output, put it in a group, and resampled the group before sending to the delete node.

The thing is, if points scope is used, the delete node will remove all the points that are not inside the bounding shape, so it's important to have points very near the edges of the circle shape. This is why I used the resample node, since it generates a lot of points.