Does alphazero support reuse-tree?

[Nightbringers]

Does alphazero support reuse-tree?

[lanctot]

After looking through the AlphaZero code quickly, it wasn't clear .. maybe/possibly?

@tewalds, do you remember if you supported this case?

[tewalds]

The MCTS implementation does, but I'm pretty sure you can't in AlphaZero since you add noise to the first layer of nodes, which distorts the shape of the tree. If you were to try to reuse the tree you'd either need to not add that noise or add it at all layers. You're welcome to try that, but that's different than the canonical AlphaZero implementation.

[Nightbringers]

Does this python version AlphaZero have the speed of c++ version?

[Nightbringers]

The MCTS implementation does, but I'm pretty sure you can't in AlphaZero since you add noise to the first layer of nodes, which distorts the shape of the tree. If you were to try to reuse the tree you'd either need to not add that noise or add it at all layers. You're welcome to try that, but that's different than the canonical AlphaZero implementation.

how can I use sub-tree in eval or play with human?