Problem with selecting center-surrounding points in grids


I’m trying to select the points with the same distances arround the center of a grid in one or more polygon.

It works fine with the whole grid and one center point, but with a splitted surface and more than one centroid it’s selecting pretty random points (at least for me) in the four areas of the surface.

I’m pretty sure the problem has something to do with the “list item” in one of the clusters, as you see above. Up to that point everything seems pretty good, so maybe there is something wrong with the format of one of the inputs?!

Thank’s in advance and please ask if I didn’t really make clear what my actual problem is!

Timo (29.1 KB)

Is this what you are trying to do? Sorted by Distance. (28.5 KB)

you will need to round coming into the sort if you want to group by same distance.

exactly, that is what’s happening inside the cluster.
what is not working is combining all points in one tree with
0;0 / 1;0 / 2;0 / 3;0 holding the center point of the quadrant
0;1 / 1;1 / 2;1 / 3;1 holding points with 1*x distance

any suggestions how to achieve that? the member index & list item combo is not working the way it is with only one grid.

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So you want to group similar distances across each quad? Your branches won’t be corresponding though, unless you round to similar numbers across all quads.

correct. if x is the distance of the (square) grid and d is the diagonal (sqrt(xx2)), each quadrant has the following branches:

center point
1x distance
1d distance
2x distance
2d distance… and so on.

each with a maximum amount of four points. pretty much whats happening in the example for the whole grid, just applied to each quadrant.
there shouldn’t be any rounding necessary since it’s all the same values or am i missing something?
thanks for your help!

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The branches are quickly going to get off on the second level, unless you are expecting null values or plan to duplicate data to fill in the gaps.

But here the branches look pretty good, or am I missing something. The distances are the same values over the different branches, so it should work fine, right?! (31.5 KB)

Here’s one way…