Video: Dab tsi yog piav qhia () hauv Python?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Python | Pandas Dataframe. Pandas piav () yog siv los saib qee cov ntsiab lus tseem ceeb xws li feem pua, txhais tau tias, std thiab lwm yam ntawm cov ntaub ntawv thav duab lossis cov lej ntawm cov lej. Thaum txoj kev no yog siv rau ib tug series ntawm txoj hlua, nws rov qab ib tug txawv tso zis uas yog qhia nyob rau hauv cov piv txwv hauv qab no.
Tsis tas li ntawd, pandas ua haujlwm hauv Python yog dab tsi?
Dab tsi txias txog Pandas yog tias nws siv cov ntaub ntawv (xws li CSV lossis TSV cov ntaub ntawv, lossis SQL database) thiab tsim ib qho Python khoom nrog kab thiab kab hu ua cov ntaub ntawv ncej uas zoo ib yam li cov lus hauv cov ntaub ntawv txheeb cais (xav Excel lossis SPSS piv txwv.
Tsis tas li ntawd, NaN txhais li cas hauv Python? nan txhais "tsis yog tus lej", tus nqi ntab uas koj tau txais yog tias koj ua ib qho kev suav uas nws tsis tuaj yeem qhia ua tus lej. Txhua qhov kev suav koj ua nrog NaN tseem yuav ua rau NaN . ua inf txhais tau tias tsis kawg. Qhov no yog vim tej kev ua haujlwm uas muaj NaN ua operand yuav rov qab los NaN.
Tsis tas li ntawd, DataFrame hauv Python yog dab tsi?
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.
Dab tsi yog pandas siv?
Pandas yog feem ntau siv rau kev kawm tshuab nyob rau hauv daim ntawv ntawm dataframes. Pandas tso cai importing cov ntaub ntawv ntawm ntau hom ntaub ntawv xws li csv, excel thiab lwm yam.
Pom zoo:
Daim ntawv qhia ncuav qab zib piav qhia nrog piv txwv yog dab tsi?
Cov kab kos ncuav qab zib yog siv hauv kev tuav cov ntaub ntawv thiab yog cov kab kos kab sib faib ua ntu uas txhua tus sawv cev rau tus nqi. Daim duab ncuav qab zib tau muab faib ua ntu (lossis 'slices') los sawv cev rau qhov sib txawv ntawm qhov ntau thiab tsawg. Piv txwv li, nyob rau hauv daim ntawv qhia ncuav qab zib no, lub voj voog sawv cev rau tag nrho cov chav kawm
Dab tsi yog kev siv piav qhia hauv MySQL?
EXPLAIN lo lus tseem ceeb yog siv thoob plaws hauv ntau yam SQL databases thiab muab cov ntaub ntawv hais txog yuav ua li cas koj SQL database ua cov lus nug. Hauv MySQL, EXPLAIN tuaj yeem siv ua ntej ntawm cov lus nug pib nrog SELECT, INSERT, DELETE, REPLACE, thiab Hloov Kho
Cov kev txwv piav qhia qee qhov kev txwv siv hauv Oracle yog dab tsi?
Cov kev txwv Oracle tau txhais raws li cov cai los khaws cov ntaub ntawv ncaj ncees hauv daim ntawv thov. Cov kev cai no yog tsim rau ib kem ntawm ib lub rooj database, thiaj li los txhais cov txheej txheem coj tus cwj pwm ntawm ib kem ntawm lub rooj thiab xyuas qhov dawb huv ntawm cov ntaub ntawv ntws mus rau hauv nws
Function Point piav qhia nws qhov tseem ceeb Dab tsi yog kev ua haujlwm taw qhia kev ntsuas?
A Function Point (FP) yog ib chav ntsuas ntsuas los qhia txog tus nqi ntawm kev lag luam kev ua haujlwm, cov ntaub ntawv xov xwm (raws li cov khoom lag luam) muab rau tus neeg siv. FPs ntsuas software loj. Lawv tau txais dav raws li kev lag luam tus qauv rau kev ua haujlwm sizing
Lub sij hawm nyob rau hauv ontology yog dab tsi yog hais txog cov lus piav qhia hierarchical thiab cov lus hais txog ib qho tshwj xeeb?
Lub schema yog ib lo lus ontology uas hais txog cov lus piav qhia hierarchical thiab cov lus hais txog ib lub npe. Ib lub npe sawv cev rau tag nrho lub tuam txhab lossis kev faib hauv ib lub tuam txhab. Ib tug cwj pwm yog ib tug yam ntxwv tshwj xeeb hais txog ib chav kawm, uas yog ib hom khoom