median between matrix column
Dear Eliza, No problem. In my solution, you can delete the sort() and get the same result. ?res1<-do.call(rbind,lapply(1:ncol(mat1[,-16]),function(i) median(stack(as.data.frame(mat1[,c(i,16)]))[,1]))) head(res1) ?# ??? [,1] #[1,] 239.0 #[2,] 238.0 #[3,] 181.5 #[4,] 244.5 #[5,] 265.0 #[6,] 212.0 A.K.
From: eliza botto <eliza_botto at hotmail.com>
To: "smartpink111 at yahoo.com" <smartpink111 at yahoo.com>
Cc: "r-help at r-project.org" <r-help at r-project.org>
Sent: Monday, October 15, 2012 9:32 AM
Subject: RE: [R] median between matrix column
To: "smartpink111 at yahoo.com" <smartpink111 at yahoo.com>
Cc: "r-help at r-project.org" <r-help at r-project.org>
Sent: Monday, October 15, 2012 9:32 AM
Subject: RE: [R] median between matrix column
Dear Arun and Jessica, thnx for your reply. it realy worked out. regards eliza > Date: Mon, 15 Oct 2012 05:55:55 -0700 > From: smartpink111 at yahoo.com > Subject: Re: [R] median between matrix column > To: eliza_botto at hotmail.com > CC: r-help at r-project.org > > HI, > May be this helps you (if I understand it correctly): > set.seed(1) > mat1<-matrix(sample(1:500,160,replace=TRUE),ncol=16) > ?res<-do.call(rbind,lapply(1:ncol(mat1[,-16]),function(i) median(sort(stack(as.data.frame(mat1[,c(i,16)]))[,1])))) > ?res > #?????? [,1] > ?#[1,] 239.0 > ?#[2,] 238.0 > ?#[3,] 181.5 > ?#[4,] 244.5 > ?#[5,] 265.0 > ?#[6,] 212.0 > ?#[7,] 228.5 > ?#[8,] 233.0 > ?#[9,] 182.5 > #[10,] 239.5 > #[11,] 233.5 > #[12,] 220.0 > #[13,] 235.0 > #[14,] 259.0 > #[15,] 227.0 > > A.K. > > > > > > ----- Original Message ----- > From: eliza botto <eliza_botto at hotmail.com> > To: "r-help at r-project.org" <r-help at r-project.org> > Cc: > Sent: Monday, October 15, 2012 8:20 AM > Subject: [R] median between matrix column > > > Dear useRs, > > 1.? ? how to calculate single median value for two columns of a matrix? > 2.? ? i have a matrix of 16 columns and 365 rows, how to calculate median between columns 1 and 16, 2 and 16, 3 and 16, 4 and 16, 5 and 16 till 15th column. is there a loop command to do the said operation? > > regards > eliza? ??? ??? ??? ? ??? ??? ? > ??? [[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list > 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. > ?