I didn't communicate my problem to R-Sig-Debian because I had never previously heard of them. Thank you for the tip. Poking through the recent archives there I see other people have had (different) trouble with the Bionic repository.
Fortunately, the instructions at https://linuxize.com/post/how-to-install-r-on-ubuntu-18-04/ worked, after I first removed the existing installation of R. All I had to do after that was reinstall about 180 packages. Is there a way to do this automatically? However, having installed "Action of the Toes" (are R releases named by Culture AIs, by any chance?) I still find > x <- runif(1000000) > y <- runif(1000000) > system.time(ifelse(x < y, x, y)) user system elapsed 0.087 0.047 0.135 > system.time(y + (x < y)*(x-y)) user system elapsed 0.035 0.008 0.042 > system.time(pmin(x,y)) user system elapsed 0.025 0.004 0.030 On Mon, 15 Jul 2019 at 12:04, Jeff Newmiller <jdnew...@dcn.davis.ca.us> wrote: > Did you ask for assistance on R-Sig-Debian? you will need to be more > explicit than below about what you actually did. FWIW I was able to do it > [1]... you might have encountered a temporary network problem. > > [1] https://cran.r-project.org/bin/linux/ubuntu/README.html > > On July 14, 2019 4:55:25 PM CDT, Richard O'Keefe <rao...@gmail.com> wrote: > >Four-core AMD E2-7110 running Ubuntu 18.04 LTS. > >The R version is the latest in the repository: > >r-base/bionic,bionic,now 3.4.4-1ubuntu1 all [installed] > > > >Why not 3.6? Because when i followed the installation instructions, > >adding > > > >deb https://cloud.r-project.org/bin/linux/ubuntu bionic-cran35/ > > > >to /etc/apt/sources.list, sudo apt update reported > > > >W: GPG error: https://cloud.r-project.org/bin/linux/ubuntu > >bionic-cran35/ > >InRelease: The following signatures couldn't be verified because the > >public > >key is not available: NO_PUBKEY 51716619E084DAB9 > >E: The repository 'https://cloud.r-project.org/bin/linux/ubuntu > >bionic-cran35/ InRelease' is not signed. > >N: Updating from such a repository can't be done securely, and is > >therefore > >disabled by default. > >N: See apt-secure(8) manpage for repository creation and user > >configuration > >details. > > > >I just repeated the test. > >> x <- runif(1000000) > >> y <- runif(1000000) > >> system.time(ifelse(x<y,x,y)) > > user system elapsed > > 0.359 0.043 0.404 > >> system.time(pmin(x,y)) > > user system elapsed > > 0.015 0.008 0.023 > >> system.time({r<-numeric(1000000);ix <- x < y; r[ix]<-x[ix]; > >r[!ix]<-y[!ix]; r}) > > user system elapsed > > 0.077 0.028 0.105 > > > >On Mon, 15 Jul 2019 at 08:00, peter dalgaard <pda...@gmail.com> wrote: > >> > >> Er, what version is this? I have (on a late 2010 MB Air!) > >> > >> > system.time(ifelse(x < y, x, y)) > >> user system elapsed > >> 0.072 0.012 0.085 > >> > >> and even > >> > >> > system.time({r<-numeric(1000000);ix <- x < y; r[ix]<-x[ix]; > >r[!ix]<-y[!ix]; r}) > >> user system elapsed > >> 0.082 0.053 0.135 > >> > >> -pd > >> > >> > >> > On 12 Jul 2019, at 15:02 , Richard O'Keefe <rao...@gmail.com> > >wrote: > >> > > >> > "ifelse is very slow"? Benchmark time. > >> >> x <- runif(1000000) > >> >> y <- runif(1000000) > >> >> system.time(ifelse(x < y, x, y)) > >> > user system elapsed > >> > 0.403 0.044 0.448 > >> >> system.time(y + (x < y)*(x - y)) > >> > user system elapsed > >> > 0.026 0.012 0.038 > >> > > >> > This appears to be a quality-of-implementation bug. > >> > > >> > > >> > On Thu, 11 Jul 2019 at 04:14, Dénes Tóth <toth.de...@kogentum.hu> > >wrote: > >> > > >> >> > >> >> > >> >> On 7/10/19 5:54 PM, Richard O'Keefe wrote: > >> >>> Expectation: ifelse will use the same "repeat vectors to match > >the > >> >> longest" > >> >>> rule that other vectorised functions do. So > >> >>> a <- 1:5 > >> >>> b <- c(2,3) > >> >>> ifelse(a < 3, 1, b) > >> >>> => ifelse(T T F F F <<5>>, 1 <<1>>, 2 3 <<2>>) > >> >>> => ifelse(T T F F F <<5>>, 1 1 1 1 1 <<5>>, 2 3 2 3 2 <<5>>) > >> >>> => 1 1 2 3 2 > >> >>> and that is indeed the answer you get. Entirely predictable and > >> >> consistent > >> >>> with > >> >>> other basic operations in R. > >> >>> > >> >>> The only tricky thing I see is that R has > >> >>> a strict vectorised ifelse(logical.vector, some.vector, > >another.vector) > >> >>> AND > >> >>> a non-strict non-vectorised if (logical.scalar) some.value else > >> >>> another.value > >> >>> AND > >> >>> a statement form if (logical.scalar) stmt.1; else stmt.2; > >> >> > >> >> Just for the records, there is a further form: > >> >> `if`(logical.scalar, stmt.1, stmt.2) > >> >> > >> >> The main problem with ifelse is that 1) it is very slow, and 2) > >the > >mode > >> >> of its return value can be unintuitive or not too predictable (see > >also > >> >> the Value and Warning sections of ?ifelse). One has to be very > >careful > >> >> and ensure that 'yes' and 'no' vectors have the same class, > >because > >> >> ifelse will not warn you at all: > >> >>> ifelse(c(TRUE, TRUE), 1:2, LETTERS[1:2]) > >> >> [1] 1 2 > >> >>> ifelse(c(TRUE, FALSE), 1:2, LETTERS[1:2]) > >> >> [1] "1" "B" > >> >> > >> >> For options instead of base::ifelse, you might find this > >discussion > >> >> helpful: > >> >> https://github.com/Rdatatable/data.table/issues/3657 > >> >> > >> >> > >> >> Cheers, > >> >> Denes > >> >> > >> >> > >> >>> > >> >>> > >> >>> On Thu, 11 Jul 2019 at 01:47, Eric Berger <ericjber...@gmail.com> > >wrote: > >> >>> > >> >>>> For example, can you predict what the following code will do? > >> >>>>> a <- 1:5 > >> >>>>> b <- c(2,3) > >> >>>>> ifelse( a < 3, 1, b) > >> >>>> > >> >>>> > >> >>>> On Wed, Jul 10, 2019 at 4:34 PM José María Mateos < > >ch...@rinzewind.org> > >> >>>> wrote: > >> >>>> > >> >>>>> On Wed, Jul 10, 2019, at 04:39, Eric Berger wrote: > >> >>>>>> 1. The ifelse() command is a bit tricky in R. Avoiding it is > >often > >a > >> >>>> good > >> >>>>>> policy. > >> >>>>> > >> >>>>> You piqued my curiosity, can you elaborate a bit more on this? > >> >>>>> > >> >>>>> -- > >> >>>>> José María (Chema) Mateos || https://rinzewind.org > >> >>>>> > >> >>>>> ______________________________________________ > >> >>>>> 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. > >> >>>>> > >> >>>> > >> >>>> [[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. > >> >>>> > >> >>> > >> >>> [[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. > >> >>> > >> >> > >> > > >> > [[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. > >> > >> -- > >> Peter Dalgaard, Professor, > >> Center for Statistics, Copenhagen Business School > >> Solbjerg Plads 3, 2000 Frederiksberg, Denmark > >> Phone: (+45)38153501 > >> Office: A 4.23 > >> Email: pd....@cbs.dk Priv: pda...@gmail.com > >> > >> > >> > >> > >> > >> > >> > >> > > > > [[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. > > -- > Sent from my phone. Please excuse my brevity. > [[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.
