Dear all,
I have data from a time span like this:
myframe <- data.frame (Timestamp=c("24.09.2012 09:00:00",
"24.09.2012 10:00:00","25.09.2012 09:00:00",
"25.09.2012
09:00:00","24.09.2012 09:00:00", "24.09.2012
10:00:00"),
Event=c(50,60,30,40,42,54) )
myframe
I want to create a new dataframe which includes in this example the data from
two successive days (in my real data I have a big time span and want data from
25 consecutive days). I understand that I can do a simple sample like this
mysample <- myframe[sample(1:nrow(myframe), 4,replace=FALSE),]
mysample
But I need the data from consecutive days in my random sample. Can anyone help
me with this?
Many thanks in advance,
Dagmar
Hi Dagmar, This will probably involve creating a variable to differentiate the two days in each data.frame: myframe$day<-as.Date(as.character(myframe$Timestamp),"%d.%m.%Y %H:%M:%S") days<-unique(myframe$day) Then just sample the two subsets and concatenate them: myframe[c(sample(which(myframe$day==days[1]),2), sample(which(myframe$day==days[2]),2)),] Jim On Fri, Dec 7, 2018 at 8:08 PM Dagmar Cimiotti <dagmar.cimiotti at ftz-west.uni-kiel.de> wrote:> > Dear all, > > I have data from a time span like this: > > myframe <- data.frame (Timestamp=c("24.09.2012 09:00:00", "24.09.2012 10:00:00","25.09.2012 09:00:00", > "25.09.2012 09:00:00","24.09.2012 09:00:00", "24.09.2012 10:00:00"), > Event=c(50,60,30,40,42,54) ) > myframe > > > I want to create a new dataframe which includes in this example the data from two successive days (in my real data I have a big time span and want data from 25 consecutive days). I understand that I can do a simple sample like this > > mysample <- myframe[sample(1:nrow(myframe), 4,replace=FALSE),] > mysample > > But I need the data from consecutive days in my random sample. Can anyone help me with this? > > > Many thanks in advance, > Dagmar > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.
Hi Jim and everyone else, Mhm, no this is not what I am looking for. I think in your way I would randomly sample two values of day 1 and of day 2. But I want the opposite: I want to randomly draw two successive (!) days and put those values in a new dataframe to continue working with them. In my real data I do have a huge time span and I want to draw 25 consecutive days. So maybe my example was a little misleading. And now that I read it again my text was, too. Sorry about that! Good try though and I am very gratefull for your good will to help me :-)?? Would anyone give another try? Dagmar Am 07.12.2018 um 10:30 schrieb Jim Lemon:> Hi Dagmar, > This will probably involve creating a variable to differentiate the > two days in each data.frame: > > myframe$day<-as.Date(as.character(myframe$Timestamp),"%d.%m.%Y %H:%M:%S") > days<-unique(myframe$day) > > Then just sample the two subsets and concatenate them: > > myframe[c(sample(which(myframe$day==days[1]),2), > sample(which(myframe$day==days[2]),2)),] > > Jim > > > On Fri, Dec 7, 2018 at 8:08 PM Dagmar Cimiotti > <dagmar.cimiotti at ftz-west.uni-kiel.de> wrote: >> Dear all, >> >> I have data from a time span like this: >> >> myframe <- data.frame (Timestamp=c("24.09.2012 09:00:00", "24.09.2012 10:00:00","25.09.2012 09:00:00", >> "25.09.2012 09:00:00","24.09.2012 09:00:00", "24.09.2012 10:00:00"), >> Event=c(50,60,30,40,42,54) ) >> myframe >> >> >> I want to create a new dataframe which includes in this example the data from two successive days (in my real data I have a big time span and want data from 25 consecutive days). I understand that I can do a simple sample like this >> >> mysample <- myframe[sample(1:nrow(myframe), 4,replace=FALSE),] >> mysample >> >> But I need the data from consecutive days in my random sample. Can anyone help me with this? >> >> >> Many thanks in advance, >> Dagmar >> >> ______________________________________________ >> R-help at 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.