Video: Dab tsi yog qhov priming nyeem Python?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Priming Nyeem . Thawj lub tswv yim ua haujlwm-ua ntej lub voj. Nws lub hom phiaj yog kom tau txais tus nqi nkag uas yuav raug kuaj los ntawm lub voj validation. yuam kev Trap / yuam kev Handler. Qee lub sij hawm input validation voj yog hu ua qhov no.
Nyob rau hauv tas li ntawd, dab tsi yog ib tug priming nyeem?
priming nyeem : Nyob rau hauv ib lub voj voog sentinel, a nyeem ua ntej lub voj xwm txheej raug kuaj. Rau lub sij hawm priming nyeem kuj tseem muaj lwm cov ntsiab lus thiab cov ntsiab lus, lub ntsiab lus thiab cov ntsiab lus uas tau hais saum toj no yog qhov qhia tias tsis siv rau kev kho mob thiab kev cai lij choj lossis lub hom phiaj tshwj xeeb.
Kuj Paub, dab tsi yog lub voj xaim hauv Python? Sentinel Loops . Hloov kho zaum kawg ntawm Sun, 16 Feb 2020 | Python Programming. Ib qho kev daws teeb meem zoo dua rau tus lej nruab nrab qhov teeb meem yog siv tus qauv uas feem ntau hu ua a sentinel xov . A sentinel xov txuas ntxiv ua cov ntaub ntawv kom txog thaum ncav cuag tus nqi tshwj xeeb uas qhia txog qhov kawg. Tus nqi tshwj xeeb hu ua tub txib.
Tsis tas li ntawd, dab tsi yog tus nqi sentinel hauv Python?
Hauv computer programming, a sentinel nqi [..] yog qhov tshwj xeeb tus nqi uas nws lub xub ntiag tau lees paub qhov kev txiav tawm ntawm lub voj uas ua cov txheej txheem (tshwj xeeb yog ntu ntu) cov ntaub ntawv. Cov sentinel nqi ua rau nws muaj peev xwm txheeb xyuas qhov kawg ntawm cov ntaub ntawv thaum tsis muaj lwm yam txhais tau tias ua li ntawd (xws li qhov qhia meej qhov loj me) muab.
Dab tsi yog lub voj voog sentinel?
A sentinel xov yog ib qho kos npe pom ntawm lub xov tooj cua uas qhia tau hais tias hauv zos ileus los ntawm qhov mob nyob ze. Yooj yim muab, nws yog qhov dilatation ntawm ib ntu ntawm cov hnyuv me. yuav tsum tau sib txawv ntawm colonic cutoff kos npe uas yog ib tug dilatation ntawm ib ntu ntawm lub plab hnyuv loj.
Pom zoo:
Dab tsi yog qhov dav thawj qhov kev tshawb nrhiav thiab qhov tob thawj qhov kev tshawb fawb?
BFS sawv rau Breadth First Search. DFS sawv cev rau Kev Tshawb Nrhiav Qhov tob. 2. BFS (Breadth First Search) siv Queue cov qauv ntaub ntawv los nrhiav txoj hauv kev luv tshaj. BFS tuaj yeem siv los nrhiav ib qhov chaw luv tshaj plaws hauv cov duab tsis hnyav, vim tias hauv BFS, peb mus txog qhov kawg uas muaj qhov tsawg kawg nkaus ntawm cov npoo los ntawm qhov chaw vertex
Dab tsi yog sparse kem Dab tsi yog qhov zoo thiab qhov tsis zoo?
Koj poob 4 bytes tsis yog ib zaug ib kab; tab sis rau txhua lub cell hauv kab uas tsis yog null. Qhov zoo ntawm SPARSE kem yog: Qhov tsis zoo ntawm SPARSE kem yog: SPARSE kem tsis tuaj yeem siv rau ntawm cov ntawv, ntext, duab, timestamp, geometry, geography lossis cov neeg siv cov ntaub ntawv teev tseg
Dab tsi yog qhov qub txeeg qub teg Dab tsi yog qhov sib txawv ntawm qhov qub txeeg qub teg piav nrog piv txwv?
Inheritance yog ib txoj hauv kev kom tau txais cov yam ntxwv thiab kev coj cwj pwm ntawm ib chav kawm los ntawm lwm chav kawm. Cov chav kawm uas cov tswv cuab tau txais qub txeeg qub teg yog hu ua chav kawm hauv paus, thiab chav kawm uas tau txais cov tswv cuab tam sim no hu ua chav derived. Inheritance siv IS-A kev sib raug zoo
Dab tsi yog qhov zoo sib xws thiab qhov txawv ntawm relays thiab PLC yog dab tsi?
Relays yog electro-mechanical keyboards uas muaj coil thiab ob hom kev sib cuag uas tsis yog NO & NC. Tab sis Programmable Logic Controller, PLC yog lub khoos phis tawj me uas tuaj yeem txiav txim siab raws li qhov kev zov me nyuam thiab nws cov tswv yim & tso tawm
Dab tsi yog qhov sib txawv ntawm qhov ntsuas qhov ntsuas thiab qhov ntsuas thib ob?
Primary index: nyob rau hauv ib tug sequentially order file, qhov Performance index uas nws search key qhia cov sequential order ntawm cov ntaub ntawv. Kuj hu ua clustering index. Secondary index: ib qho Performance index uas nws qhov tseem ceeb tshawb nrhiav qhia qhov kev txiav txim sib txawv ntawm qhov kev txiav txim ntawm cov ntaub ntawv. Kuj hu ua non-clustering index