I-Pandas yilayibrari yePython esetyenziswa ngokubanzi kwintsimi yokuguqulwa kwedatha kunye nohlalutyo. Ibonelela ngolwakhiwo lwedatha kunye nemisebenzi efunekayo ukusebenza kunye nedatha eyakhiweyo ngaphandle komthungo. Enye yezinto ezininzi ezinikezelayo kukukwazi ukujoyina iitafile ezinezitshixo ezingezona ezikhethekileyo, ezinokuthi zibe yimfuneko eqhelekileyo kwizicelo eziphathekayo. Kweli nqaku, siya kungena kwisisombululo sale ngxaki, sihlolisise inkcazo yesinyathelo-nge-nyathelo yekhowudi esetyenziselwa ukujoyina izinto ze-DataFrame ze-pandas kunye nezitshixo ezingezona ezikhethekileyo, kwaye sixoxe ngamathala eencwadi kunye nemisebenzi echaphazelekayo kule nkqubo.
intshayelelo
Ukujoyina iitheyibhile ngumsebenzi osisiseko owenziweyo ekusetyenzisweni kwedatha kunye nemisebenzi yohlalutyo. Kwiimeko ezithile, kusenokufuneka sidibanise iitheyibhile kwisitshixo esingeyodwa, esinokuzisa imingeni. Nangona kunjalo, ukusebenza kunye nethala leencwadi lePython elinamandla, iipandas, kusivumela ukuba sisombulule le ngxaki ngobuchule sisebenzisa ukusebenza kwayo okuguquguqukayo.
Ukudibanisa iiPandas DataFrames ezinamaqhosha angengowodwa
Ukujoyina iiFrames zeDatha kwiipandas, sinokusebenzisa `ukudibanisa()` umsebenzi, oxhasa ukudibanisa kumaqhosha angawodwa. Nangona kunjalo, kubalulekile ukuqonda ukuba isiphumo sokujoyina izitshixo ezingezona zodwa zinokwahluka kunokuba kulindelwe, njengoko kunokukhokelela kwimveliso ye-cartesian, okunokubangela ukwanda okukhulu kwenani lemiqolo kwisiphumo seDataFrame.
Nantsi isikhokelo senyathelo nenyathelo lokusebenzisa `ukudibanisa()` umsebenzi ukudibanisa iiFrames zeDatha ngezitshixo ezingazodwa:
import pandas as pd
# Create sample DataFrames
df1 = pd.DataFrame({"key": ["A", "B", "A", "C"], "value": [1, 2, 3, 4]})
df2 = pd.DataFrame({"key": ["A", "B", "A", "D"], "value2": [5, 6, 7, 8]})
# Perform the merge operation
result = df1.merge(df2, on="key", how="inner")
Kulo mzekelo ungentla, siqala ukungenisa ilayibrari yepandas kwaye senze iisampuli ezimbini zeDathaFrames (df1 kunye ne-df2). Emva koko, sisebenzisa `ukudibanisa()` umsebenzi ukujoyina iiFrames zeDatha kwikholamu "yesitshixo", equlethe amaxabiso angawodwanga (A kunye no-B bayaphindwa). Ipharamitha ethi `njani` imiselwe ku "ngaphakathi", njengoko sifuna ukugcina kuphela iirowu ezinezitshixo ezihambelanayo kuzo zombini iiFrames zeDatha.
Ukuqonda umsebenzi wokudibanisa iPandas
Umsebenzi `ukudibanisa()` kwipanda sisixhobo esinamandla kwaye sibhetyebhetye ukwenza imisebenzi yokudibanisa itafile. Ukongeza ekujoyineni iiFrames zeDatha ngezitshixo ezingazodwa, ixhasa amanqanaba ahlukeneyo okwenziwa ngokwezifiso, ikuvumela ukuba ube nolawulo olupheleleyo kwisiphumo seDathaFrame.
Umsebenzi `ukudibanisa()` uneeparamitha ezininzi ezibalulekileyo ezifana nezi:
- khohlo kwaye kunene: Ezi ziiDatha zeDatha eziza kudityaniswa.
- on: Ikholamu ekufuneka isetyenziselwe ukujoyina i-DataFrames. Oku kunokuba ligama lekholamu enye okanye uluhlu lwamagama eekholamu xa udibanisa kwimiqolo emininzi.
- njani: Ichaza uhlobo lokudibanisa ekufuneka lwenziwe. Iinketho ziquka 'ekhohlo', 'ekunene', 'ngaphandle', kunye 'nangaphakathi'. Ukungagqibeki ngu'ngaphakathi'.
- izimamva: Le yi-tuple yezimamva zemitya ukuze zisetyenziswe kwiikholam ezithelelanayo. Isimamva esingagqibekanga ngu _x seDataFrame esekhohlo kunye _y yeSakhelo seDatha sasekunene.
Ezi parameters zinokulungiswa ngokweemfuno zakho ukwenza iintlobo ezahlukeneyo zokudityaniswa kwemisebenzi kunye nokwenza ngokwezifiso iziphumo.
Imisebenzi efanayo kwiPandas
Ngaphandle kokudibanisa ()` umsebenzi, iipanda zikwabonelela neminye imisebenzi yokudibanisa iiFrames zeDatha ngeendlela ezahlukeneyo, ezinje:
- concat(): Lo msebenzi usetyenziselwa ukudibanisa iiFrames zeDatha kwi-axis ethile. Ungalawula ukudityaniswa ngokukhankanya iiparamitha ezahlukeneyo ezinje nge-axis, ukujoyina, kunye nezitshixo.
- Joyina (): Le yindlela efanelekileyo ekhoyo kwizinto ze-DataFrame ukwenza imisebenzi yokudibanisa. Ngokwesiseko sisisongelo esirhangqe ukudibanisa() umsebenzi, ngesakhelo seData sasekhohlo esithathwa njengomfowuneli weDataFrame.
Ukuqukumbela, ngokusebenzisa i-pandas `dibanisa ()` umsebenzi, ungajoyina ngokulula iiFrames zeDatha ngezitshixo ezingazodwa. Iqela elityebileyo leeparameters ezikhoyo 'kukudibanisa()` umsebenzi unikezela ngolawulo olupheleleyo phezu kwenkqubo yokudibanisa, ukulungiselela iimfuno ezahlukeneyo zokuguqulwa kwedata. Ithala leencwadi le-pandas liyaqhubeka lisisixhobo esiyimfuneko kubahlalutyi bedatha kwaye libonelela ngemisebenzi eyahlukeneyo yokudibanisa kunye nokukhohlisa iiFrames zeDatha ngokufanelekileyo.
