Pandas 文本数据方法 find( ) rfind( ) index( ) rindex( )

Series.str.find(sub, start=0, end=None)????????,????
Series.str.rfind(sub, start=0, end=None)????????,????Series.str.index(sub, start=0, end=None)????????,????,???????
Series.str.rindex(sub, start=0, end=None)????????,????,???????
??:
sub : ???
start : ??,???
end : ??,???
??:
??Series/??Index

import pandas as pds = pd.Series(['A', 'B', 'C', 'Aaba', 'Baca', 'CABA', 'dog', 'cat'])print(s.str.find("a"))0   -11   -12   -13    14    15   -16   -17    1dtype: int64print(s.str.rfind("a"))0   -11   -12   -13    34    35   -16   -17    1dtype: int64