I-formula ye-Bailey-Borwain-Plouffe, evumela ukuba ukhuphe nayiphi na i-hexadecimal ethile okanye idijithi yokubini ye-pi ngaphandle kokubala kwangaphambili (irekhodi yangoku yayisetwa kusetyenziswa i-algorithm ye-Chudnovsky, jonga ngezantsi kokusikwa)
I-Google Compute Engine computing cluster ibale elona nani likhulu lamanani kwi-pi ngeentsuku ezili-121 koomatshini abangama-25, ibeka irekhodi yehlabathi elitsha: 31,4 yetriliyoni yeendawo zedesimali. Esi sisihlandlo sokuqala isoftware yelifu efumanekayo esidlangalaleni isetyenziselwa ukubala i-pi yobu bukhulu.
Irekhodi liya kubhalwa egameni lika-Emma Haruka Iwao ukusuka kwicandelo eliphezulu le-computing kwi-Google. Yayinguye owayesebenzisa isiseko seLifu likaGoogle ukwenza ikhompyuter. Ingxelo yehlabathi yangaphambili ibekwe nguPeter Troub kwi-2016, wabala inani ukuya kwi-22,4 yetriliyoni yedijithi. , eyayikwaxhaswa ngumqeshi.
NjengoTrub, injineli kaGoogle isebenzise i-y-cruncher ekubaleni. Le nkqubo isebenzisa , i-algorithm ekhawulezayo yokubala i-pi. Emva kwi-80s ngokwethu yayisetyenziselwa ukubala indawo yedesimali yebhiliyoni.
Ngapha koko, i-algorithm isekwe kwipropathi yokudibanisa ngokukhawuleza koluhlu lwe-hypergeometric:
U-Emma Haruka Iwao waba nomdla kwinombolo "yomlingo" emva kokufunda ngayo kwiklasi yezibalo esikolweni. Wired. Eyunivesithi, omnye wonjingalwazi wakhe, uDaisuke Takahashi, ubambe irekhodi lamanani amaninzi yenani elibalwe kusetyenziswa ikhompyutha enkulu. Namhlanje, irekhodi linokusetwa phantse nayiphi na injineli enomdla onokufikelela kwizixhobo ezinzulu zekhompyuter kunye nokugcinwa kwediski enkulu (ukugcina umphumo wokubala). Inkqubo yenziwe ngo-2009 yenzelwe ukubala izinto eziguquguqukayo zemathematika ezifana ne-pi. Ixhasa imisonto emininzi kunye netriliyoni-scale ranges. Le nkqubo ithengise ngokufanelekileyo ukubalwa kwezinto ezingaguqukiyo.
"Udinga ikhompyuter enkulu kakhulu ukophula irekhodi yehlabathi," utshilo u-Iwao. "Awunakuyenza kwikhompyuter evenkileni, ke abantu bebesakha iimoto eziqhelekileyo." NgoSeptemba ka-2018, u-Iwao waqala ukuqwalasela indlela inkqubo yokubala eya kusebenza ngayo ngaphaya koluhlu lwerekhodi. Kwangoko kwacaca ukuba ingxaki ephambili iya kuba yimali yedatha ekufuneka igcinwe. Ngenxa yoko, kwavela ukuba umphumo obaliweyo uthatha i-170 terabytes. Esikhundleni sokwakha iseva yesiko, njengabangaphambili bakhe, intombazana yasebenzisa isiseko se-Google Cloud.
U-Iwao wachola oomatshini abangama-25: “Kodwa endaweni yokucofa elo qhosha lomatshini izihlandlo ezingama-25, ndizenzele lona,” uyacacisa. "Ungayenza kwimizuzu embalwa, kodwa ukuba ufuna iikhompyuter ezininzi, kuya kuthatha iintsuku ezininzi ukuseta yonke into." U-Iwao ke waqhuba i-y-cruncher kwezo matshini angama-121 ngokuqhubekayo kangangeentsuku ezili-25.
Ukuze izibalo zichaneke, oomatshini benyani kwakufuneka basebenze rhoqo. Injineli yafakela inkqubo yokubeka iliso eyayiza kumlumkisa ukuba kukho into engahambi kakuhle, umzekelo, malunga nokusilela ngequbuliso komnye woomatshini ababonakalayo. Ukusilela nje kube kanye- nokuba yimizuzu embalwa-kunokubeka esichengeni yonke inkqubo yekhompyuter ukuba ayilulo ugcino.
"I-Cruncher kunye neLifu likaGoogle zineenkqubo zokugcina, kwaye ndizibeke ukuze ukwazi ukuthatha ngoko nangoko iikopi zezo diski ngaphandle kokuyeka ukubala," utshilo u-Iwao. Le datha yakhutshelwa kwaye yagcinwa ngaphandle, kwezinye iidrives, njenge-snapshots.
“Ekuqaleni, bekukho iiparitha ezimbalwa endizitshintshileyo, ezinje ngokuba yidatha engakanani onokufunda okanye ukuyibhala ngexesha elinye, kunye nokuba imida ingatshintsha njani xa usondezile,” utshilo u-Iwao.
Njengoko inani lamadijithi landa, umthamo weefayile waba mkhulu, kwaye ubunzima bezibalo banda ngokungaqhelekanga. Oku kwenza ukubala kokuqala kube nzima kakhulu xa u-Iwao wayezama ukubala ukuba ungakanani na uvimba womatshini wenyani awayeza kuwufuna kwiprojekthi.
Ngoku zombini izibalo kunye nokuqinisekiswa kwesiphumo kugqityiwe: ii-algorithms ezimbini ezisisiseko zakhiwe kwi-y-cruncher - enye yokubala i-pi ngokwayo, kwaye enye yokuqinisekisa. I-algorithm yokuqinisekisa isebenza ngokuhambelana nokubala, kodwa ibala idijithi enye kuphela, ukwenzela ukuba irekhodi libhaliswe ngokusemthethweni.
Kwithiyori, irekhodi elitsha lehlabathi linokusetwa ngokuthatha nje ifayile yangaphambili kunye nokusebenzisa ifomula ye-Bailey-Borwain-Plouffe ukubala enye inombolo. Kodwa oku kuya kuphikisana nemithetho yokubhalisa iirekhodi zehlabathi: kunokwenzeka ukuba, umfaki-sicelo ngamnye kufuneka aqale ukubala ukususela ekuqaleni. Njengokhetho: phucula impumelelo yangaphambili nge-N%, engenakwenziwa ngokweformula ye-Bailey-Borwain-Plouffe.
umthombo: www.habr.com
