Flatten - Pls explain

Can somebody explain what flatten means and how it is use?

1 Like

see here

Flatten simply takes a list of lists (with any number of sublists) and “flattens” it into a single, 1-dimensional list.
There is also a Flatten (n) node which flattens your list of lists by combining n dimensions of a list.

1 Like

why is there a need to flatten?

if you for example collect all windows, doors and columns… but you dont care if they should be diveded into sublists. If the case is that you want to add a comment to all elements you have collected, then it is handy that the list is flattern. You can solve this issue using another method than flattern, but it is a simple and fast way to do it.

List flatten is a easy way to make sure you do not have to worry too much about list structures matching into a input node.

Thank you guys…