Hi It is documented behaviour.
"An empty index selects all values: this is most often used to replace all the entries but keep the attributes." so I presume that changing it could break huge amount of code. The only workaround could be to check "z" before using it for indexing. e.g. > if(length(z)==0) z <- length(y) + 1 > y[-z] [1] 1 2 3 > Cheers Petr > -----Original Message----- > From: R-help <r-help-boun...@r-project.org> On Behalf Of Nick Wray via R- > help > Sent: Tuesday, January 8, 2019 10:29 AM > To: r-help <r-help@r-project.org> > Subject: [R] Why does R do this? > > y<-c(1,2,3) > z<-which(y>3) > z > y<-y[-z] > y > > In the work I'm doing I often have this situation and have to make sure that I > condition on z being non-zero as y is now numeric(0) rather than the set > c(1,2,3). Why does R do this? Wouldn't it be more sensible for R to simply > leave the host set unchanged if there are no elements to take out? > > Any thoughts? > > Thanks, Nick Wray > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. Osobní údaje: Informace o zpracování a ochraně osobních údajů obchodních partnerů PRECHEZA a.s. jsou zveřejněny na: https://www.precheza.cz/zasady-ochrany-osobnich-udaju/ | Information about processing and protection of business partner’s personal data are available on website: https://www.precheza.cz/en/personal-data-protection-principles/ Důvěrnost: Tento e-mail a jakékoliv k němu připojené dokumenty jsou důvěrné a podléhají tomuto právně závaznému prohláąení o vyloučení odpovědnosti: https://www.precheza.cz/01-dovetek/ | This email and any documents attached to it may be confidential and are subject to the legally binding disclaimer: https://www.precheza.cz/en/01-disclaimer/ ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
