TreeMap

TreeMap[f, tree] applies f to the data of each subtree of tree.

• TreeMap[f, tree, levelspec] applies f to the data of subtrees on levels of tree specified by levelspec.
• TreeMap[f, tree, levelspec -> elems] applies f to the elements elems of subtrees on levels specified by levelspec.
• TreeMap[f] represents an operator form of TreeMap that can be applied to a tree.

Examples

Apply function to all nodes:

TreeMap[f, Tree[a, {Tree[b, {}], Tree[c, {}]}]]

Map at specific level:

TreeMap[StringLength, tree, {2}]

Please visit the official Wolfram Language Reference for more details.