TreeReplacePart

TreeReplacePart[tree, pos -> new] gives a tree in which the subtree of tree at the position specified by pos is replaced with new.

• TreeReplacePart[tree, {pos1 -> new1, pos2 -> new2, ...}] replaces subtrees at positions specified by posi with newi.
• TreeReplacePart[tree, {pos1, pos2, ...} -> new] replaces all subtrees at positions specified by posi with new.
• TreeReplacePart[tree, {{pos1,1, pos1,2, ...} -> new1, ...}] replaces subtrees at positions specified by {posi,1, posi,2, ...} with newi.
• TreeReplacePart[pos -> new] represents an operator form of TreeReplacePart that can be applied to a tree.

Examples

tree = Tree[a, {Tree[b, {c, d}], e}];
TreeReplacePart[tree, {1, 2} -> x]

Please visit the official Wolfram Language Reference for more details.