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Video: Koj ua li cas thiaj tsim tau DataFrame index?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Muaj ob txoj hauv kev los teeb tsa DataFrame index
- Siv qhov parameter inplace = Tseeb los teeb tsa DataFrame index tam sim no.
- Muab cov ntaub ntawv tshiab tsim DataFrame rau qhov sib txawv thiab siv qhov sib txawv ntawd ntxiv los siv cov txiaj ntsig Indexed.
Nyob rau hauv kev hwm rau qhov no, yuav ua li cas koj teem ib qhov Performance index rau cov ntaub ntawv ncej?
Rau teeb ib kem as qhov ntsuas rau a DataFrame , siv DataFrame . set_index() muaj nuj nqi, nrog rau kab npe dhau los ua kev sib cav. Koj tuaj yeem ua tau teeb tsa MultiIndex nrog ntau kab hauv cov qhov ntsuas . Hauv qhov no, dhau qhov array ntawm kab npe uas xav tau rau qhov ntsuas , rau set_index() method.
Tom qab ntawd, lo lus nug yog, koj tsim DataFrame hauv pandas li cas? Pandas DataFrame yog ob-dimensional loj-mutable, muaj peev xwm heterogeneous tabular cov ntaub ntawv qauv nrog sau npe axes (kab thiab kab). A Cov ntaub ntawv ncej yog ob-seem cov ntaub ntawv qauv, piv txwv li, cov ntaub ntawv yog raws li nyob rau hauv ib tug tabular zam nyob rau hauv kab thiab kab.
Kuj paub, koj tsim cov ntaub ntawv li cas?
Rau tsim pandas DataFrame Hauv Python, koj tuaj yeem ua raws li cov qauv no: ntshuam pandas li pd cov ntaub ntawv = {'Thawj Kem Lub Npe': ['Tus nqi thib ib', 'Tus nqi thib ob',], 'Lub Npe thib ob': ['Tus nqi thib ib', ' thib ob nqi',],. } df = np. DataFrame (cov ntaub ntawv, kab = ['Lub Npe Lub Npe', 'Lub Npe thib ob',])
DataFrame index yog dab tsi?
Indexing hauv pandas txhais tau tias tsuas yog xaiv cov kab tshwj xeeb thiab kab ntawm cov ntaub ntawv los ntawm a DataFrame . Indexing tuaj yeem txhais tau tias xaiv tag nrho cov kab thiab qee kab, qee cov kab thiab tag nrho cov kab, lossis qee qhov ntawm txhua kab thiab kab. Indexing tuaj yeem raug hu ua Subset Selection.
Pom zoo:
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