Using mutate followed by summarise in this case is completely unnecessary. a <- ( lDf %>% dplyr::group_by( Provider ) %>% dplyr::summarise( u = min( CollectionDate ) ,, v = max( CollectionDate ) ) )
On August 21, 2020 2:41:26 AM PDT, Eric Berger <ericjber...@gmail.com> wrote: >Hi Eberhard, >Here is one possibility using dplyr. > >library(dplyr) >set.seed(3) > >## set up some fake data >dtV <- as.Date("2020-08-01") + 0:4 >x <- sample(dtV,20,repl=TRUE) >provider <- sample(LETTERS[1:3],20,repl=TRUE) >lDf <- >data.frame(Provider=provider,CollectionDate=x,stringsAsFactors=FALSE) > >## get min/max date for each provider >a <- lDf %>% dplyr::group_by( Provider ) %>% >dplyr::mutate( minDt=min(CollectionDate), maxDt=max(CollectionDate)) >%>% > dplyr::summarize( u = min(minDt), v = max(maxDt) ) > >## get the common interval >c(max(a$u), min(a$v)) > ># [1] "2020-08-02" "2020-08-04" > >HTH, >Eric > > >On Fri, Aug 21, 2020 at 12:34 PM Rasmus Liland <j...@posteo.no> wrote: > >> On 2020-08-21 09:03 +0200, Dr Eberhard Lisse wrote: >> > Hi, >> > >> > I have a small test sample with lab >> > reports (PAP smears) from a number of >> > different providers. These have >> > Collection Dates and the relevant >> > columns glimpse() something like >> > this: >> > >> > $ Provider <chr> "Dr C", "Dr D", "Dr C", "Dr D" >> > $ CollectionDate <chr> "2016-11-03", "2016-11-02", "2016-11-03", >> "2016-11-03" >> > >> > I am looking to find (filter) the >> > reports which were collected in the >> > time period common to all providers? >> > >> > Something like >> > >> > the largest First Common CollectionDate >> > and >> > the smallest Last Common CollectionDate >> > >> > How would I do that? >> > >> > I can of course do this "manually", ie >> > collect all Providers and their first >> > and last Collection dates and then >> > find the Common First and Last one, >> > but wonder if there is an elegant way >> > of doing this :-)-O >> >> Dear Eberhard, >> >> Is each report in a csv file with those >> two columns, and you want to unify them >> into a dataframe with CollectionDate >> along the rows, and other details for >> each provider along the columns? This >> can be done with various apply calls and >> reshape. Can you please subset some >> more example data here using dput. It >> makes it so much easier. >> >> /Rasmus >> ______________________________________________ >> 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. -- Sent from my phone. Please excuse my brevity. ______________________________________________ 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.