# Node question (Vector math - length)

Hello.
I downloaded the file from the post and looked at how the node was configured, but I didn’t understand it, so I posted the question.

As far as I know, only selected the z-axis line as the switch node, and I think they put the length.
It seems to define the length of x,y,z using that length, but I don’t understand how to calculate that value.
Is the connection to the Combine XYZ node other than the length value?

If the Edge vector dot (0,0,1) is 0 then the edge is horizontal, so, the Switch filters out the Width (`W`, which is just the length of that edge) which gets captured on that face’s edges as `Capture=(W+W+0+0)/4` (quads), so `W=Capture*2`. Then get Height (`H`) using the Area input, since `Area=W*H`, `H=Area/W`. Approximate depth (`D`) to `sqrt(Area)`. Those dimensions (`W,D,H`) then gets captured per face.

Hope that helps.

Good luck!

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I understand how it’s calculated.
But I don’t understand why is it that the capture attribute node adds the length of the width and the length of the height and then the division 4 is done? Does the capture attribute node calculate the average length?
I thought only the length of the horizon was captured in the capture attribute node. Also, even if capture it, I never thought there would be an operation to find the length of the perimeter

Kinda. Because there are 4 edges per face. If it was a n-gon with 6 edges, then it would be divided by 6. This method only works with vertically aligned rectangular quads. So, this method is figuring out the width by using that fact.

Good luck!

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I’m here to confirm it’s this, also apparently there’s a new node in beta (or alpha ?) that will map an instance to a quad face, so this would become obsolete.

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I didn’t know this information. Thank you for the news!