1.set_index
DataFrame可以通过set_index方法,可以设置单索引和复合索引。
DataFrame.set_index(keys, drop=True, append=False, inplace=False, verify_integrity=False) append添加新索引,drop为False,inplace为True时,索引将会还原为列In [307]: dataOut[307]: a b c d0 bar one z 1.01 bar two y 2.02 foo one x 3.03 foo two w 4.0 In [308]: indexed1 = data.set_index('c') In [309]: indexed1Out[309]: a b dc z bar one 1.0y bar two 2.0x foo one 3.0w foo two 4.0 In [310]: indexed2 = data.set_index(['a', 'b']) In [311]: indexed2Out[311]: c da b bar one z 1.0 two y 2.0foo one x 3.0 two w 4.0
2.reset_index
reset_index可以还原索引,从新变为默认的整型索引
DataFrame.reset_index(level=None, drop=False, inplace=False, col_level=0, col_fill=”) level控制了具体要还原的那个等级的索引 drop为False则索引列会被还原为普通列,否则会丢失In [318]: dataOut[318]: c da b bar one z 1.0 two y 2.0foo one x 3.0 two w 4.0 In [319]: data.reset_index()Out[319]: a b c d0 bar one z 1.01 bar two y 2.02 foo one x 3.03 foo two w 4.0
转自:https://blog.csdn.net/jingyi130705008/article/details/78162758