tff.learning.optimizers.build_adamw

Returns a tff.learning.optimizers.Optimizer for AdamW.

tff.learning.optimizers.build_adamw(
    learning_rate: optimizer.Float,
    beta_1: optimizer.Float = 0.9,
    beta_2: optimizer.Float = 0.999,
    epsilon: optimizer.Float = 1e-07,
    weight_decay: optimizer.Float = 0.004
) -> tff.learning.optimizers.Optimizer

The AdamW optimizer is based on Decoupled Weight Decay Regularization

The update rule given learning rate lr, epsilon eps, accumulator acc, preconditioner s, weigh decay lambda, iteration t, weights w and gradients g is:

acc = beta_1 * acc + (1 - beta_1) * g
s = beta_2 * s + (1 - beta_2) * g**2
normalization = sqrt(1 - beta_2**t) / (1 - beta_1**t)
w = w - lr * (normalization * acc / (sqrt(s) + eps) + lambda * w)

learning_rate A positive float for learning rate.
beta_1 A float between 0.0 and 1.0 for the decay used to track the previous gradients.
beta_2 A float between 0.0 and 1.0 for the decay used to track the magnitude (second moment) of previous gradients.
epsilon A small non-negative float, used to maintain numerical stability.
weight_decay A non-negative float, governing the amount of weight decay. When set to 0, this recovers Adam.