Cov txheej txheem:
Video: Koj ua li cas nrog NA qhov tseem ceeb hauv R?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Thaum koj import dataset los ntawm lwm cov ntaub ntawv txheeb cais cov tsis muaj nuj nqis tej zaum yuav raug coded nrog tus lej, piv txwv li 99. Yuav kom cia R paub tias yog a tsis muaj nqi koj yuav tsum tau recode nws. Lwm qhov tseem ceeb muaj nuj nqi hauv R rau deal nrog qhov tseem ceeb uas ploj lawm yog na . omit() uas tshem tawm cov kev soj ntsuam tsis tiav.
Yog li ntawd, koj yuav ua li cas nrog NA hauv R?
NA options in R
- omit thiab na. exclude: xa rov qab cov khoom nrog kev soj ntsuam tshem tawm yog tias lawv muaj qhov tseem ceeb uas ploj lawm; Qhov sib txawv ntawm kev tshem tawm thiab tsis suav nrog NAs tuaj yeem pom hauv qee qhov kev kwv yees thiab cov haujlwm seem.
- pass: xa cov khoom tsis hloov.
- tsis ua: rov qab cov khoom tsuas yog tias nws tsis muaj qhov tseem ceeb uas ploj lawm.
Ib yam li ntawd, koj yuav ua li cas los daws cov ntaub ntawv uas ploj lawm hauv R? Muaj ntau txoj hauv kev los daws qhov tseem ceeb ntawm txoj kev categorical.
- Tsis quav ntsej kev soj ntsuam ntawm qhov tseem ceeb uas ploj lawm yog tias peb tab tom cuam tshuam nrog cov ntaub ntawv loj thiab cov ntaub ntawv tsawg dua muaj qhov tsis muaj txiaj ntsig.
- Tsis quav ntsej qhov sib txawv, yog tias nws tsis tseem ceeb.
- Tsim qauv los kwv yees qhov tseem ceeb uas ploj lawm.
- Kho cov ntaub ntawv uas ploj lawm tsuas yog lwm qeb.
Ib yam li ntawd ib tug yuav nug, koj yuav ua li cas teev qhov tseem ceeb hauv R?
Hauv R , tsis muaj nuj nqis yog sawv cev los ntawm lub cim NA (tsis muaj). Ua tsis tau tus nqi (piv txwv li, faib los ntawm xoom) yog sawv cev los ntawm lub cim NaN (tsis yog tus lej). Tsis zoo li SAS, R siv tib lub cim rau tus cwj pwm thiab tus lej cov ntaub ntawv . Rau kev xyaum ua haujlwm nrog cov ntaub ntawv uas ploj lawm , sim qhov no ntawm kev ntxuav cov ntaub ntawv hauv R.
Na Rm txhais li cas hauv R?
Thaum siv dataframe muaj nuj nqi na . rm ib hauv r yog hais txog lub logical parameter uas qhia cov haujlwm seb puas yuav tshem tawm NA tus nqi los ntawm kev suav. Nws yog lus txhais tau tias NA tshem tawm. Nws tsis yog kev ua haujlwm lossis kev ua haujlwm. Nws tsuas yog ib qho parameter siv los ntawm ob peb dataframe functions.
Pom zoo:
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