Hi As Jeff said for data frames you can use split. If you insist to work with matrices, the principle is similar but you cannot use split.
mat <- matrix(1:20, 5,4) mat [,1] [,2] [,3] [,4] [1,] 1 6 11 16 [2,] 2 7 12 17 [3,] 3 8 13 18 [4,] 4 9 14 19 [5,] 5 10 15 20 # factor for splitting fac <- factor(c(1,2,1,2,1)) > fac [1] 1 2 1 2 1 Levels: 1 2 #splitting matrix according to the factor levels > mat[which(fac==1), ] [,1] [,2] [,3] [,4] [1,] 1 6 11 16 [2,] 3 8 13 18 [3,] 5 10 15 20 > mat[which(fac==2), ] [,1] [,2] [,3] [,4] [1,] 2 7 12 17 [2,] 4 9 14 19 Cheers Petr > -----Original Message----- > From: R-help <r-help-boun...@r-project.org> On Behalf Of Jeff Newmiller > Sent: Wednesday, January 5, 2022 8:57 AM > To: Faheem Jan <faheemja...@yahoo.com>; R-help <r-help@r-project.org> > Subject: Re: [R] splitting data matrix into submatrices > > Please reply all so the mailing list is included in the discussion. I don't > do 1:1 > tutoring and others can chime in if I make a mistake. > > I would say you don't understand what my example did, since it doesn't care > how many columns are in your data frame. If you are in fact working with a > matrix, then convert it to a data frame. > > As for continuing to help you... you need to provide a minimal reproducible > example with a small sample data set if what I showed you isn't helping. > > [1] http://stackoverflow.com/questions/5963269/how-to-make-a-great-r- > reproducible-example > > [2] http://adv-r.had.co.nz/Reproducibility.html > > On January 4, 2022 10:44:39 PM PST, Faheem Jan > <faheemja...@yahoo.com> wrote: > >I understand what you have done, it can easily apply in the case of vector > information mean each day having a single observation. But in my case I have > 24 observations each day, I want to convert the matrix into two submatrices > for weekdays and the other for weekends. So please suggest to me anyway > that how I do this? > > > > On Wednesday, January 5, 2022, 11:10:34 AM GMT+5, Jeff Newmiller > <jdnew...@dcn.davis.ca.us> wrote: > > > > A lot of new R users fail to grasp what makes data frames more useful than > matrices, or use data frames without even realizing they are not using > matrices. > > > >This is important because there are more tools for manipulating data frames > than matrices. One tool is the split function... if you have a vector of > values > identifying how each row should be identified you can give that to the split > function with your data frame and it will return a list of data frames (2 in > this > case). > > > >v <- rep( 0:6, length=1826 ) > >wkv <- ifelse( v < 5, "Weekday", "Weekend" ) ans <- split( DF, wkv ) > >ans$Weekday ans$Weekend > > > >Note that this is a fragile technique for generating wkv though... usually > there will be a column of dates that can be used to generate wkv more > consistently if your data changes. > > > >Please read the Posting Guide... using formatted email can cause readers to > not see what you sent. Use plain text email format... it is a setting in > your > email client. > > > >On January 4, 2022 7:52:34 PM PST, Faheem Jan via R-help <r-help@r- > project.org> wrote: > >>I have data in a matrix form of order 1826*24 where 1826 represents the > days and 24 hourly observations on each data. My objective is to split the > matrix into working (Monday to Friday) and non-working (Saturday and > Sunday) submatrices. Can anyone help me that how I will do that splitting > using R? > >> > >> > >> [[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.
______________________________________________ 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.