Change StatItem.number from int to float

Author: Chengqian-Zhang

deepmd/utils/env_mat_stat.py

@@ -28,15 +28,15 @@ class StatItem:
 
     Parameters
     ----------
-    number : int
+    number : float
         The total size of given array.
     sum : float
         The sum value of the matrix.
     squared_sum : float
         The sum squared value of the matrix.
     """
 
-    def __init__(self, number: int = 0, sum: float = 0, squared_sum: float = 0) -> None:
+    def __init__(self, number: float = 0, sum: float = 0, squared_sum: float = 0) -> None:
         self.number = number
         self.sum = sum
         self.squared_sum = squared_sum