Joining Breps - inconsistent results

Hi guys,

I’m a relatively newbie to Grasshopper but enjoying having a go. I’ve gotten my definition to a point but having some problems with something that isn’t making any sense to me. Why are these two components yielding different results? I don’t understand…

Thanks in advance,


Architectural model (292.1 KB)

I understand why you ask the question and the answer is that The upper join sometimes output 2 open Brep. So the list will have more than 80 elements. You could group to suppress this problem.
You can also use Treesloth to renumber path.
{i,j} will become {k}

Thanks for that Laurent and apologies for the slow reply. Yes, I think that is the answer. Sorry for asking a noobie question but I am a beginner with Grasshopper. I’m not sure how to use the group component to do what you’re suggesting. I can download the treesloth plugin too but not sure if I’ll be able to get it to behave as I’d like. Any pointers appreciated. Thanks.


Group is very simple to use and you are not a noobi when I see your definition.
Let sumarize. You have data in tree, but each branch has not always a single element. If you plug a list number you will see that most of the time output is one but sometime 2. SO if you plug a group there will be just one element (a group) in each branch.
I hope it is more clear. Don’t hesitate to ask here for clarification.

Thanks again for that - I guess my real problem is that once I’ve grouped the data like that I’m unable to unroll the breps. clues?