max是什么意思

python中idx是什么意思_在python中滚动idxmax（）？

参见⽂档：

还有⼀些很好的例⼦：In[18]:df=DataFrame(randn(1000,4),index=_range('20000101',periods=1000),

columns=list('ABCD'))

In[19]:g_apply(df,30,lambdax:Series(x).idxmax())

Out[19]:

DatetimeIndex:1000entries,2000-01-0100:00:00to2002-09-2600:00:00

Freq:D

Datacolumns(total4columns):

A971non-nullvalues

B971non-nullvalues

C971non-nullvalues

D971non-nullvalues

dtypes:float64(4)

In[47]:g_apply(df,30,lambdax:Series(x).idxmax()).tail(30)

Out[47]:

ABCD

2002-08-282432621

2002-08-292322520

2002-08-302212419

2002-08-312102318

2002-09-012062917

2002-09-021952816

2002-09-031842715

2002-09-041732614

2002-09-051622513

2002-09-061512412

2002-09-071402311

2002-09-

2002-09-091212219

2002-09-101111208

2002-09-111010197

2002-09-1299186

2002-09-1388175

2002-09-1477164

2002-09-1566153

2002-09-1655142

2002-09-1744131

2002-09-1833120

2002-09-19221111

2002-09-20111010

2002-09-210099

2002-09-22272588

2002-09-23262477

2002-09-24252366

2002-09-25242255

2002-09-26232944

仅供参考，使⽤rolling_max(df,30)来获取特定范围内的最⼤值可能会更好，这正是我收集到的您所追求的