Grasshopper: Empty Generic Data from Explode Tree

Hello. I am following a youtube tutorial to make a script in grasshopper. I checked the steps for several times but not sure why my Branch 1 of Explode Tree is empty.

Besides, as shown on the image I attached, one face of the platonic solid will further subdivide when I increase the number of Data 1. Meanwhile, that one on the youtube video doesn’t seem to change.

Please feel free to leave any possible solutions. Many thanks!!

The video I mentioned: Grasshopper Tutorial | Geodesic Sphere (Dome) - YouTube

Try “Graft” the R output of Merge

Just as a general point, it’s worth understanding that the data coming out of the Shift Paths component is just a single branch hence the wire itself is not dashed but a double tramline. So that’s why the explode tree only gives one output.

In the earlier stages, Grasshopper will try to match up two lists (so called ‘corresponding indexing’) when you feed a component two lists of data like that, so you have to graft one input as Kim has shown so that for every triangular curve, it subdivides each one according to all the data in the input (in this case, two numbers made in the merge).

This is kind of the problem with following YouTube tutorials. They can be tremendously useful, but they can sometimes skip stages or assume basic knowledge so you don’t get a deeper understanding. I cannot recommend going through the ‘Grasshopper Primer’ highly enough to understand the way components handle lists and trees. Anyway, I’ll get off my soapbox now : )

Thank you very much, Kim. The “Graft” works but I agree to what John said as well. More problems appear afterwards. So I guess I’d better learn more about the basic knowledge of grasshopper before going through this youtube tutorial.

Still, thank you very much!

Hi John. I got what you mean about the youtube tutorials. It is totally true that I have encountered numerous problems whenever I try to follow a youtube tutorial. In fact, I am still processing all these concepts you mentioned. Still, thank you very much for your time and I will try to comprehend the concepts so that I can be able to handle the “Grasshopper Primer” soon.

Thank you very much!

No problem, best of luck with your learning. Also, try to aim for youtube tutorials where they actually explain things rather than play music and assume you just follow along a bit like a zombie (not picking on the author of the videos here, but they can make you feel like you get somewhere without really knowing what you’re doing!).

It’s always funny, I mean David Rutten’s (the author of Grasshopper) basic tutorials, I think 14 of them, have only about 1000 views on them and they really are an explanation of the basics from the horse’s mouth. Definitely worth a quick view (skipping through sections you already know) before tackling more complicated definitions. Here is a link.

Best of luck with your learning!

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Thank you for your advice!