Merge remote-tracking branch 'origin/master'

train.py

@@ -133,9 +133,13 @@ def train(hyp):
             with open(results_file, 'w') as file:
                 file.write(ckpt['training_results'])  # write results.txt
 
+        # epochs
         start_epoch = ckpt['epoch'] + 1
-        assert opt.epochs > start_epoch, '%s has already trained %g epochs. --epochs must be greater than %g' % \
-                                         (opt.weights, ckpt['epoch'], ckpt['epoch'])
+        if epochs < start_epoch:
+            print('%s has been trained for %g epochs. Fine-tuning for %g additional epochs.' %
+                  (opt.weights, ckpt['epoch'], epochs))
+            epochs += ckpt['epoch']  # finetune additional epochs
+
         del ckpt
 
     # Mixed precision training https://github.com/NVIDIA/apex