Select a specific item in data tree

Hello,

I´m new to grasshopper and trying to understand how to use data trees.

So I´d like to select a specific item in data tree. I want to use a component like List Item, but I´d like to type in the item like {0;0;0}[5] by using for example a Panel.

I´ve tried the component Split Tree and attaching it to a Panel typing {0;0;0}[5]. but even though a single point is seemingly selected, trying to treat it like a single point doesn’t work? If you attach a circle to the point the circle component will say “this component run 48 times” not 1 time. Also trying to create a line between this point and another point doesn’t work. Or maybe Im doing something wrong.

I can technically use List Item, but what if I wanna select something in a more systematic way or in a specific pattern? I don’t feel List item is enough. But maybe in combination with other components?

Sorry for my bad knowledge

Split Tree preserves Data Tree structure of unselected items with place holders(null)for many reasons. You can get rid of these by using Clean Tree.
Or, you can also try Cherry Picker.


Split & Clean Tree.gh (10.6 KB)

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I find that a combination of tree statistics, list item, and Tree Branch are pretty effective in traversing geometry that is in a structured tree format.
You may also want to search for posts on Relative item/items to explore how to connect various points from 1 data branch, (could think of it as a column/row), to other “relative” branches.

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Maybe [Tree Branch] + [List Item] …?

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Me too.


vuTreeList_2017_Jan19a.gh (20.0 KB)

Cluster vTrE:

Cluster vList:

vList_2017_Jan19a

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tree item does something similar

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Thank you :slight_smile: I feel this is closest to what I wanted to achieve!

Split Tree combined with Clean Tree.

As you say, Clean Tree gets rid of the unnecessary values that I don’t want. Also, in your script you use an Expression component, but one can also use the Panel component. I can type in many different expressions here to get interesting results.

Thank you to all answers! I´m happy that there are many different solutions for achieving the same thing. Different problems may need different solutions.

Split Tree combined with Clean Tree.

You can see here that Clean Tree gets rid of the unnecessary values I don’t want so I can get a specific value on the grid. Now, finally, the Circle component says it only ran once. I can also create lines using the points on the grid.

Furthermore, Split Tree together with Panel or Expression component makes it possible to put in an expression of your choice. You can then achieve interesting results.
Here I combine two grids to create lines between several points(created with different expressions):

I can for example type these expressions into the Panel
{0;0;?}[0 to 3 and !2]
{0;0;5}[>3]


I felt other solutions didn’t always give me the opportunity to create very flexible use of expressions. But all the answers in this thread did solve my problem in one way or the other.

Wow!
That’s an “analogical” way to navigate trees!
Next step what? Quantum stuff?
I love grasshopper!

This tool has always been essential for me to visually inspect data trees. I use it all the time.