访问大熊猫系列timedeltas的`.days`

时间:2017-08-02 18:33:54

标签: python python-3.x pandas timedelta

pandas TimedeltaIndex有一个属性days,可用于其他正常dtypes(float64等)的操作:

import pandas as pd
from pandas.tseries import offsets
idx1 = pd.date_range('2017-01', periods=10)
idx2 = idx1 + offsets.MonthEnd(1)
tds = idx2 - idx1

print(tds.days - 2)
Int64Index([28, 27, 26, 25, 24, 23, 22, 21, 20, 19], dtype='int64')

但是当tds转换为系列(显式或作为DataFrame列)时,它会丢失此属性。

print(pd.Series(tds).days)
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-115-cb20b4d368f4> in <module>()
----> 1 print(pd.Series(tds).days)

C:\Users\bsolomon\Anaconda3\lib\site-packages\pandas\core\generic.py in __getattr__(self, name)
   3079             if name in self._info_axis:
   3080                 return self[name]
-> 3081             return object.__getattribute__(self, name)
   3082 
   3083     def __setattr__(self, name, value):

AttributeError: 'Series' object has no attribute 'days'

访问.days需要转换回Index

print(pd.Index(pd.Series(tds)).days)
Int64Index([30, 29, 28, 27, 26, 25, 24, 23, 22, 21], dtype='int64')

访问此属性的方式是否比上述转换更直接?

1 个答案:

答案 0 :(得分:4)

使用.dt访问者:

print(pd.Series(tds).dt.days)

输出:

0    30
1    29
2    28
3    27
4    26
5    25
6    24
7    23
8    22
9    21
dtype: int64