Python 将cumxxx(总和,最小值…)应用于数据帧中大小不同的窗口
我想对数据帧中大小不同的窗口应用Python 将cumxxx(总和,最小值…)应用于数据帧中大小不同的窗口,python,pandas,cumsum,rolling-computation,Python,Pandas,Cumsum,Rolling Computation,我想对数据帧中大小不同的窗口应用cumxxx操作。 考虑到下列投入: import pandas as pd from random import seed, randint from collections import OrderedDict p5h = pd.period_range(start='2020-02-01 00:00', end='2020-02-04 00:00', freq='5h', name='p5h') p1h = pd.period_range(start='2
cumxxx
操作。
考虑到下列投入:
import pandas as pd
from random import seed, randint
from collections import OrderedDict
p5h = pd.period_range(start='2020-02-01 00:00', end='2020-02-04 00:00', freq='5h', name='p5h')
p1h = pd.period_range(start='2020-02-01 00:00', end='2020-02-04 00:00', freq='1h', name='p1h')
seed(1)
values = [randint(0,10) for p in p1h]
df = pd.DataFrame({'Values' : values}, index=p1h)
p5h_st_as_series = p5h.start_time.to_series()
df['OpeneningPeriod'] = df.apply(
lambda x: p5h.to_series().loc[p5h_st_as_series.index <=
x.name.start_time].index[-1],
axis=1)
此处,将在定义的5小时期间应用cumxxx
。它可以是不同长度的,因为窗口可以是一天周期(有些带有DST),也可以是一个月周期(不是一个月内的固定小时数)
我想要的结果是:
df_result.head(11)
Values OpeneningPeriod Cumsum
p1h
2020-02-01 00:00 2 2020-02-01 00:00 2 <- cumsum starts with a new period
2020-02-01 01:00 9 2020-02-01 00:00 11
2020-02-01 02:00 1 2020-02-01 00:00 12
2020-02-01 03:00 4 2020-02-01 00:00 16
2020-02-01 04:00 1 2020-02-01 00:00 17
2020-02-01 05:00 7 2020-02-01 05:00 7 <- cumsum starts with a new period
2020-02-01 06:00 7 2020-02-01 05:00 14
2020-02-01 07:00 7 2020-02-01 05:00 21
2020-02-01 08:00 10 2020-02-01 05:00 31
2020-02-01 09:00 6 2020-02-01 05:00 37
2020-02-01 10:00 3 2020-02-01 10:00 3 <- cumsum starts with a new period
df_结果头(11)
值开启周期累计数
p1h
2020-02-01 00:00 2 2020-02-01 00:00 2如果需要分组,按5H
窗口按DatetimeIndex
使用cumsum
:
df['Cumsum'] = df.resample('5H')['Values'].cumsum()
或:
groupby
应该是一个很好的起点:
df['Cumsum'] = df.groupby('OpeneningPeriod')['Values'].cumsum()
它给出:
Values OpeneningPeriod Cumsum
p1h
2020-02-01 00:00 2 2020-02-01 00:00 2
2020-02-01 01:00 9 2020-02-01 00:00 11
2020-02-01 02:00 1 2020-02-01 00:00 12
2020-02-01 03:00 4 2020-02-01 00:00 16
2020-02-01 04:00 1 2020-02-01 00:00 17
2020-02-01 05:00 7 2020-02-01 05:00 7
2020-02-01 06:00 7 2020-02-01 05:00 14
2020-02-01 07:00 7 2020-02-01 05:00 21
2020-02-01 08:00 10 2020-02-01 05:00 31
2020-02-01 09:00 6 2020-02-01 05:00 37
2020-02-01 10:00 3 2020-02-01 10:00 3
2020-02-01 11:00 1 2020-02-01 10:00 4
2020-02-01 12:00 7 2020-02-01 10:00 11
2020-02-01 13:00 0 2020-02-01 10:00 11
2020-02-01 14:00 6 2020-02-01 10:00 17
2020-02-01 15:00 6 2020-02-01 15:00 6
...
谢谢@jezrael,我保留了您的第一个解决方案,并重新采样。您知道重采样是否也可以保留第一个值,但保持索引不变?(即将第一个值复制到以下4行)如果我应用first(),索引将以“5H”频率重新采样。所以中间行不会被保留。@pierre_j-我想你需要df['first']=df.resample('5H')['Values'].transform('first')
print (df.head(11))
Values OpeneningPeriod Cumsum
p1h
2020-02-01 00:00 2 2020-02-01 00:00 2
2020-02-01 01:00 9 2020-02-01 00:00 11
2020-02-01 02:00 1 2020-02-01 00:00 12
2020-02-01 03:00 4 2020-02-01 00:00 16
2020-02-01 04:00 1 2020-02-01 00:00 17
2020-02-01 05:00 7 2020-02-01 05:00 7
2020-02-01 06:00 7 2020-02-01 05:00 14
2020-02-01 07:00 7 2020-02-01 05:00 21
2020-02-01 08:00 10 2020-02-01 05:00 31
2020-02-01 09:00 6 2020-02-01 05:00 37
2020-02-01 10:00 3 2020-02-01 10:00 3
df['Cumsum'] = df.groupby('OpeneningPeriod')['Values'].cumsum()
Values OpeneningPeriod Cumsum
p1h
2020-02-01 00:00 2 2020-02-01 00:00 2
2020-02-01 01:00 9 2020-02-01 00:00 11
2020-02-01 02:00 1 2020-02-01 00:00 12
2020-02-01 03:00 4 2020-02-01 00:00 16
2020-02-01 04:00 1 2020-02-01 00:00 17
2020-02-01 05:00 7 2020-02-01 05:00 7
2020-02-01 06:00 7 2020-02-01 05:00 14
2020-02-01 07:00 7 2020-02-01 05:00 21
2020-02-01 08:00 10 2020-02-01 05:00 31
2020-02-01 09:00 6 2020-02-01 05:00 37
2020-02-01 10:00 3 2020-02-01 10:00 3
2020-02-01 11:00 1 2020-02-01 10:00 4
2020-02-01 12:00 7 2020-02-01 10:00 11
2020-02-01 13:00 0 2020-02-01 10:00 11
2020-02-01 14:00 6 2020-02-01 10:00 17
2020-02-01 15:00 6 2020-02-01 15:00 6
...