python - Pandas 中一列的平均距离

Question

我有一个这样的数据框:

sample = pd.DataFrame({'a': [10, 16, 7, 2, 5]})

如何找到“a”列的平均距离？例如，10 和 16 之间的平均距离 = (10 + 6)/2 = 8

Answer 1

在您描述的数学之后，它相当于“下一个值除以 2”。所以我们通过移动系列然后 / 2 来获得下一个值将它们减半:

# data itself
>>> sample

    a
0  10
1  16
2   7
3   2
4   5

# shift the values upwards by 1 unit so 2nd becomes 1st etc.
# and the last becomes NaN as there is nothing below it to replace
>>> sample.shift(-1)

      a
0  16.0
1   7.0
2   2.0
3   5.0
4   NaN

# per your formula
>>> sample.shift(-1) / 2

     a
0  8.0
1  3.5
2  1.0
3  2.5
4  NaN