diff --git a/train.py b/train.py
index 0b459286..8d3a25d7 100644
--- a/train.py
+++ b/train.py
@@ -136,6 +136,7 @@ def train():
     # lf = lambda x: 1 - x / epochs  # linear ramp to zero
     # lf = lambda x: 10 ** (hyp['lrf'] * x / epochs)  # exp ramp
     # lf = lambda x: 1 - 10 ** (hyp['lrf'] * (1 - x / epochs))  # inverse exp ramp
+    # lf = lambda x: 0.5 * (1 + math.cos(x * math.pi / epochs))  # cosine https://arxiv.org/pdf/1812.01187.pdf
     # scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
     # scheduler = lr_scheduler.MultiStepLR(optimizer, milestones=range(59, 70, 1), gamma=0.8)  # gradual fall to 0.1*lr0
     scheduler = lr_scheduler.MultiStepLR(optimizer, milestones=[round(opt.epochs * x) for x in [0.8, 0.9]], gamma=0.1)