我的数据框的某个事件的时间为from
和to
列。
import pandas as pd
import numpy as np
data = [
[np.datetime64('2019-06-25T03:30'), np.datetime64('2019-06-25T05:30')],
[np.datetime64('2019-06-25T22:30'),np.datetime64('2019-06-26T04:30')],
]
df = pd.DataFrame(data, columns = ['from', 'to'])
看起来像这样
from to
0 2019-06-25 03:30:00 2019-06-25 05:30:00
1 2019-06-25 22:30:00 2019-06-26 04:30:00
请注意第二行如何跨越日期边界。我想将to
和from
时间设置为午夜将该行一分为二
预期结果:
from to
0 2019-06-25 03:30:00 2019-06-25 05:30:00
1 2019-06-25 22:30:00 2019-06-26 00:00:00
2 2019-06-26 00:00:00 2019-06-26 04:30:00
我考虑过应用一个可以进行拆分的函数,但这似乎不起作用。
def split_days(row):
# if it's the same day, do not split
if row['from'].date == row['to'].date :
return row
# if different days, make two rows
# first day until mignight and second day from midnight onwards
else:
row2 = row.copy(deep=True)
row['to']=row['to'].replace(hour=0, minute=0, second=0, microsecond=0)
row2['from']=row2['to'].replace(hour=0, minute=0, second=0, microsecond=0)
return pd.concat([row, row2], axis=1).T # <= this is certainly incorrect
df.apply(split_days, axis=1)
如何将函数应用于DF的每一行,并用几个新行替换它?
答案 0 :(得分:1)
pd.date_range
,floor
,ceil
delta = pd.Timedelta(days=1)
def ranger(F, T): return pd.date_range(F.ceil('D'), T.floor('D')).union([F, T])
def dzippr(D): return zip(D, D[1:])
pd.DataFrame(
[[f, t]
for F, T in zip(df['from'], df['to'])
for f, t in dzippr(ranger(F, T))],
columns=df.columns
)
from to
0 2019-06-25 03:30:00 2019-06-25 05:30:00
1 2019-06-25 22:30:00 2019-06-26 00:00:00
2 2019-06-26 00:00:00 2019-06-26 04:30:00