diff --git a/PolarPointBEV/metric.py b/PolarPointBEV/metric.py
index 272654e..1f93f17 100644
--- a/PolarPointBEV/metric.py
+++ b/PolarPointBEV/metric.py
@@ -51,12 +51,9 @@ def __init__(self, num_classes):
 	def update(self, a, b):
 		n = self.num_classes
 		if self.mat is None:
-			# 创建混淆矩阵
 			self.mat = torch.zeros((n, n), dtype=torch.int64, device=a.device)
 		with torch.no_grad():
-			# 寻找GT中为目标的像素索引
 			k = (a >= 0) & (a < n)
-			# 统计像素真实类别a[k]被预测成类别b[k]的个数(这里的做法很巧妙)
 			inds = n * a[k].to(torch.int64) + b[k]
 			self.mat += torch.bincount(inds, minlength=n**2).reshape(n, n)
 
@@ -89,4 +86,4 @@ def __str__(self):
 				acc_global.item() * 100,
 				['{:.1f}'.format(i) for i in (acc * 100).tolist()],
 				['{:.1f}'.format(i) for i in (iu * 100).tolist()],
-				iu.mean().item() * 100)
\ No newline at end of file
+				iu.mean().item() * 100)