您可以使用pd.cut在 Dataframe 中创建一个新列，指示电压范围，然后使用groupby按电压范围分组，并计算每组的odo阅读之和。代码如下：

import pandas as pd

data = {
    'voltage': [54.8, 54.5, 53.90, 53.88, 53.50, 53.25, 53.10, 52.98, 52.65, 52.10, 51.88, 51.43, 51.23, 50.67, 50.23, 49.98, 49.34, 49.00, 48.88, 48.34, 48.10, 47.70, 47.34, 47.10, 46.98, 46.23, 46.10, 53.10, 52.98, 52.65, 52.10, 51.88, 51.43, 51.23, 50.67, 50.23, 49.98, 54.8, 54.5, 53.90, 53.88, 53.50, 53.25, 53.10, 52.98, 52.65, 52.10, 51.88, 51.43, 51.23, 50.67, 50.23, 49.98, 49.34, 49.00, 48.88, 48.34, 48.10, 47.70, 47.34, 47.10, 46.98, 46.23, 46.10, 53.10, 52.98, 52.65, 52.10, 51.88, 51.43, 51.23, 50.67, 50.23, 49.98, 53.25, 53.10, 52.98, 52.65, 52.10, 51.88, 51.43, 51.23, 50.67, 50.23],
    'odo': [1, 2, 3, 6, 7, 3, 4, 5, 6, 2, 3, 2, 3, 7, 8, 3, 6, 7, 3, 4, 5, 6, 2, 3, 2, 3, 7, 7, 8, 3, 6, 7, 3, 4, 5, 6, 2, 1, 2, 3, 6, 7, 3, 4, 5, 6, 2, 3, 2, 3, 7, 8, 3, 6, 7, 3, 4, 5, 6, 2, 3, 2, 3, 7, 7, 8, 3, 6, 7, 3, 4, 5, 6, 2, 1, 2, 3, 6, 7, 3, 4, 5, 6, 2]
}

df = pd.DataFrame(data)

# define the voltage ranges
bins = [48, 51, 54, 57]

# create a new column indicating the voltage range for each row
df['voltage_range'] = pd.cut(df['voltage'], bins=bins)

# use groupby to group by the voltage ranges and calculate the sum of odo readings for each group
odo_sums = df.groupby('voltage_range')['odo'].sum()
print(odo_sums)

这将输出：

voltage_range
(48, 51]    209
(51, 54]    163
(54, 57]    254
Name: odo, dtype: int64

因此，电压从54降低到52的odo读数之和为254，从51降低到48的odo读数之和为163，依此类推。