xnd*_*ndr 5 python dataframe pandas
我正在尝试将日期时间索引重新采样为每小时数据.我也希望重新采样到月底.
所以给出以下内容df:
data = np.arange(6).reshape(3,2)
rng = ['Jan-2016', 'Feb-2016', 'Mar-2016']
df = pd.DataFrame(data, index=rng)
df.index = pd.to_datetime(df.index)
0 1
2016-01-01 0 1
2016-02-01 2 3
2016-03-01 4 5
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我知道我可以通过以下方式将其重新计算为小时索引:df = df.resample('H').ffill()但是,当我调用df它时,它会被切断2016-03-01.我从根本上让指数从运行1/1/2016到3/31/2016带有每小时粒度.
2015-03-31如果最后一个索引是月初,我该如何将其扩展到月末.
更新:
In [37]: (df.set_index(df.index[:-1].union([df.index[-1] + pd.offsets.MonthEnd(0)]))
....: .resample('H')
....: .ffill()
....: .head()
....: )
Out[37]:
0 1
2016-01-01 00:00:00 0 1
2016-01-01 01:00:00 0 1
2016-01-01 02:00:00 0 1
2016-01-01 03:00:00 0 1
2016-01-01 04:00:00 0 1
In [38]: (df.set_index(df.index[:-1].union([df.index[-1] + pd.offsets.MonthEnd(0)]))
....: .resample('H')
....: .ffill()
....: .tail()
....: )
Out[38]:
0 1
2016-03-30 20:00:00 2 3
2016-03-30 21:00:00 2 3
2016-03-30 22:00:00 2 3
2016-03-30 23:00:00 2 3
2016-03-31 00:00:00 4 5
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解释:
In [40]: df.index[-1] + pd.offsets.MonthEnd(0)
Out[40]: Timestamp('2016-03-31 00:00:00')
In [41]: df.index[:-1].union([df.index[-1] + pd.offsets.MonthEnd(0)])
Out[41]: DatetimeIndex(['2016-01-01', '2016-02-01', '2016-03-31'], dtype='datetime64[ns]', freq=None)
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旧的错误答案:
In [77]: df.resample('M').ffill().resample('H').ffill().tail()
Out[77]:
0 1
2016-03-30 20:00:00 2 3
2016-03-30 21:00:00 2 3
2016-03-30 22:00:00 2 3
2016-03-30 23:00:00 2 3
2016-03-31 00:00:00 4 5
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