Graft tree

Hello every one !
One question :whait is the utilite of the component ‘‘Graf tree’’?
whait is the meaning the hug at the top of the panel?

It is a data tree operation; I’d suggest spending 1 hour to get into the basics of it in the video below:


thanks ! Pleas,could you explaine me the hug in the top of panel ? sometimes we see 2 values in the hug ,1values ,could you enlight me please?
Yours truly !

can you send me a screenshot of the hug you are asking about?


This is called data branch. So in grasshopper data is sorted into multiple branches like a tree so to call an item with the tree you need to select the branch and then an item within the branch.

I know it sounds confusing a little bit but I suggest putting an effort to learn it and you can master all types of data management within grasshopper.

I suggest watching this video to learn more.

Also this book is a must read

Graft is important to match lists of data:

Suppose you have 2 curves, and you divide them. So now you have 2 lists of points with 11 points each.
You want to create vertical lines on each curve, with different heights. Say 10m and 5m.

Your 2 lists are together in the same ‘data tree’

If you input 10 and 5 from sliders without graft you will get the wrong result:

What is going on here? The first 2 vertical lines have 10m and the rest 5m. Why? Because GH matches the first value (10m) with the first point. Then the second value (5m) with the second point. And so on. But it has no more values, so it repeats the last one (5m). So all other lines will be 5m high.

Then it does the same with the other list.

When you Graft, you are telling GH that value 10 will go with the first list of points and value 5 will go with the second list of points.

Correct result!

Here the def if you want to check yourself. (12.8 KB)