first commit

ssd/solver/build.py

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+import torch
+
+from .lr_scheduler import WarmupMultiStepLR
+
+
+def make_optimizer(cfg, model, lr=None):
+    lr = cfg.SOLVER.BASE_LR if lr is None else lr
+    return torch.optim.SGD(model.parameters(), lr=lr, momentum=cfg.SOLVER.MOMENTUM, weight_decay=cfg.SOLVER.WEIGHT_DECAY)
+
+
+def make_lr_scheduler(cfg, optimizer, milestones=None):
+    return WarmupMultiStepLR(optimizer=optimizer,
+                             milestones=cfg.SOLVER.LR_STEPS if milestones is None else milestones,
+                             gamma=cfg.SOLVER.GAMMA,
+                             warmup_factor=cfg.SOLVER.WARMUP_FACTOR,
+                             warmup_iters=cfg.SOLVER.WARMUP_ITERS)