python - 索引包含开区间的 Pandas 数据帧

Question

我如何索引如下所示的数据框:

i   BDia         
0   (0.025, 0.05]    0.006726
    (0.05, 0.075]    0.006650
    (0.075, 0.1]     0.005531
    (0.1, 0.125]     0.005792
    (0.125, 0.15]    0.006576
    (0.15, 0.175]    0.000141
1   (0.025, 0.05]    0.007256
    (0.05, 0.075]    0.006929
    (0.075, 0.1]     0.006551
    (0.1, 0.125]     0.007238
    (0.125, 0.15]    0.007008
    (0.15, 0.175]    0.006658

其中i和BDia是多级索引。例如，我如何选择开区间为 (0.025, 0.05] 的所有值？

Answer 1

我认为你需要Interval然后选择像 MultiIndex 和 loc 或使用 slicers :

a = pd.Interval(left=0.025, right=0.05)
#or
#a = pd.IntervalIndex.from_tuples([(0.025, 0.05)])[0]
print (a)
(0.025, 0.05]

df = df.loc[:, [a]]
print (df)
i               
0  (0.025, 0.05]    0.006726
1  (0.025, 0.05]    0.007256
Name: col, dtype: float64

<小时/>

a = df.loc[:, a]
print (a)
i
0    0.006726
1    0.007256
Name: col, dtype: float64

<小时/>

idx = pd.IndexSlice
a = df.loc[idx[0, a]]
print (a)
0.006726