大约有 43,300 项符合查询结果（耗时：0.0354秒） [XML]
Pandas count(distinct) equivalent
...()
Example:
In [2]: table
Out[2]:
CLIENTCODE YEARMONTH
0 1 201301
1 1 201301
2 2 201301
3 1 201302
4 2 201302
5 2 201302
6 3 201302
In [3]: table.groupby('YEARMONTH').CLIENTCODE.nunique()
Out[3...
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Explicitly select items from a list or tuple
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154
list( myBigList[i] for i in [87, 342, 217, 998, 500] )
I compared the answers with python ...