in flsim/optimizers/local_optimizers.py [0:0]
def step(self, closure=None):
"""Performs a single optimization step.
Arguments:
closure (callable, optional): A closure that reevaluates the model
and returns the loss.
"""
loss = None
if closure is not None:
with torch.enable_grad():
loss = closure()
for group in self.param_groups:
weight_decay = group["weight_decay"]
momentum = group["momentum"]
dampening = group["dampening"]
nesterov = group["nesterov"]
for p in group["params"]:
if p.grad is None:
continue
d_p = p.grad
param_state = self.state[p]
if "global_model" not in param_state:
param_state["global_model"] = torch.clone(p.data).detach()
if weight_decay != 0:
d_p = d_p.add(p, alpha=weight_decay)
if momentum != 0:
if "momentum_buffer" not in param_state:
buf = param_state["momentum_buffer"] = torch.clone(d_p).detach()
else:
buf = param_state["momentum_buffer"]
buf.mul_(momentum).add_(d_p, alpha=1 - dampening)
if nesterov:
d_p = d_p.add(buf, alpha=momentum)
else:
d_p = buf
d_p.add_(p.data - param_state["global_model"], alpha=self.cfg.mu)
p.add_(d_p, alpha=-group["lr"])
return loss