Appending to a Tree

Is there a way to append to a data tree? Or, in other words, combine two data trees (with matching path structures) but not merge them?

For example, I have two trees:

(Paths = 2)
{0;1}
{0;2}

and

(Paths = 3)
{0;1}
{0;2}
{0;3}

and I would like to get

(Paths = 5)
{0;1}
{0;2}
{0;3}
{0;4}
{0;5}

Any ideas?

Replies to This Discussion

Permalink Reply by taz on November 18, 2009 at 12:47pm

Sameer,

Whether two trees are merged or appended all depends on path names. To do what you want you would still use the merge component (or feed both trees to the same input), but you would need to keep track of the path names yourself.

You can use the Replace Branches component to rename.

For instance:

(Paths = 2)
{0;1}
{0;2}

and

(Paths = 3)
{0;1} rename {0;3}
{0;2} rename {0;4}
{0;3} rename {0;5}

Does this make enough sense to get you started?

-taz

Permalink Reply by Sameer Kumar on November 18, 2009 at 2:18pm

Taz,

Yes, that makes sense and I was able to do this. I was hoping that there would be a simpler way but yes, the above works.

Thank you for the help!

Permalink Reply by TiM on November 18, 2009 at 1:01pm

"Flatten" both paths ----> "Merge streams" ---> "Graft Tree". I think, it should work ;)

Permalink Reply by Sameer Kumar on November 18, 2009 at 2:20pm

It may work if there is only one item in each path. As soon as there are multiple and different number of items in every path, the above method will not apply. Taz's method is the way to go.

Thanks in any case!

Permalink Reply by CarloMaria Ciampoli on November 18, 2009 at 2:50pm

I've never been crazy about the Replace Branches component

Permalink Reply by Sameer Kumar on November 18, 2009 at 3:53pm

Carlo,
Very interesting and useful. This is the first use of the "Explode Tree" component and the "Flatten Path" variable that I have seen!

However, I have upto 125 paths that I am splitting and then re-combining for various purposes. With the "Replace Branches", I can create and replace several paths using series/ranges... That may be more efficient.

It may be a tool worth putting on the wishlist for David... I can see that there may be other situations when such a tool may become useful.

Permalink Reply by CarloMaria Ciampoli on November 18, 2009 at 3:58pm

Sameer,
can you post an image of the Masks and Replacement Paths you are using?
I'm curious to see what your solution is.

Permalink Reply by Sameer Kumar on November 18, 2009 at 4:20pm

Sure... here you go:

Permalink Reply by Benjamin Golder on April 4, 2010 at 12:52am

I am trying to do something almost exactly like this, but I cannot seem to get "Replace Branches" to work. What am I doing wrong?

Permalink Reply by Benjamin Golder on April 4, 2010 at 12:56am

Never mind. Now I see why everyone was trying to remove the curly brackets.

Permalink Reply by Benjamin Golder on April 4, 2010 at 1:23am

for others who end up here looking for solutions:

http://www.grasshopper3d.com/forum/topics/depositing-lists-into-bra...

Permalink Reply by taz on November 18, 2009 at 5:00pm

This is something that has been bugging me so I'll post it here (where no one will find it...)

Can anyone show me the proper use of the SubString expression to remove curly brackets? I'm using 2 separate functions instead instead of one...