On 12-07-31 02:38 PM, Claudia Penaloza wrote:
> Thank you very much Rui (and Eloi for your input)... this is (the very
> simplified version of) what I will end up using:
Could we get the extended version ? Because right now, I don't know why
you need such complicated code that can be done in 1 line.
> J <- 10
> N <- 10
> y <- matrix(0,N,J)
> cols <- rep(c(TRUE, TRUE, FALSE, FALSE), 3)[seq_len(J)]
> for(j in which(cols)){
> for (q in 1:N){
> if(j %% 2){
> y[q,j]=1
> }else{y[q,j]=2}
> }
> }
> for(j in which(!cols)){
> for (q in 1:N){
> if(j %% 2){
> y[q,j]="A"
> }else{y[q,j]="B"}
> }
> }
>
There is no need for a double loop (on N) :
J <- 10
N <- 10
y <- matrix(0,N,J)
cols <- rep(c(TRUE, TRUE, FALSE, FALSE), 3)[seq_len(J)]
for(j in which(cols)){
if(j %% 2){
y[,j]=1
}else{y[,j]=2}
}
for(j in which(!cols)){
if(j %% 2){
y[,j]="A"
}else{y[,j]="B"}
}
if you really wants to use this code.
Cheers,
Eloi
> Cheers,
> Claudia
> On Mon, Jul 30, 2012 at 5:38 PM, Mercier Eloi <emerc...@chibi.ubc.ca
> <mailto:emerc...@chibi.ubc.ca>> wrote:
>
> Or, assuming you only have 4 different elements :
>
> mat<- matrix(rep(c(1,2,"A", "B"),each=10),10,10, byrow=F)
> mat2 <- as.data.frame(mat)
>
> mat
>
> [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
> [1,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [2,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [3,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [4,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [5,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [6,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [7,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [8,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [9,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [10,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
>
> mat2
> V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
>
> 1 1 2 A B 1 2 A B 1 2
> 2 1 2 A B 1 2 A B 1 2
> 3 1 2 A B 1 2 A B 1 2
> 4 1 2 A B 1 2 A B 1 2
> 5 1 2 A B 1 2 A B 1 2
> 6 1 2 A B 1 2 A B 1 2
> 7 1 2 A B 1 2 A B 1 2
> 8 1 2 A B 1 2 A B 1 2
> 9 1 2 A B 1 2 A B 1 2
> 10 1 2 A B 1 2 A B 1 2
>
> Cheers,
>
> Eloi
>
>
> On 12-07-30 04:28 PM, Rui Barradas wrote:
>
> Hello,
>
> Maybe something along the lines of
>
> J <- 10
> cols <- rep(c(TRUE, TRUE, FALSE, FALSE), 3)[seq_len(J)]
> for(i in which(cols)) { do something }
> for(i in which(!cols)) { do something else }
>
> Hope this helps,
>
> Rui Barradas
>
> Em 31-07-2012 00 <tel:31-07-2012%2000>:18, Claudia Penaloza
> escreveu:
>
> Dear All,
> I would like to apply two different "for loops" to each
> set of four columns
> of a matrix (the loops here are simplifications of the
> actual loops I will
> be running which involve multiple if/else statements).
> I don't know how to "alternate" between the loops
> depending on which column
> is "running through the loop" at the time.
> ## Set up matrix
> J <- 10
> N <- 10
> y <- matrix(0,N,J)
> ## Apply this loop to the first two of every four columns
> ([,1:2],
> [,5:6],[,9:10], etc.)
> for (q in 1:N){
> for(j in 1:J){
> if(j %% 2){
> y[q,j]=1
> }else{y[q,j]=2}
> }
> }
> ## Apply this loop to the next two of every four columns
> ([,3:4],[,7:8],[,11:12], etc.)
> for (q in 1:N){
> for(j in 1:J){
> if(j %% 2){
> y[q,j]="A"
> }else{y[q,j]="B"}
> }
> }
> I want to get something like this (preferably without the
> quotes):
>
> y
>
> [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
> [1,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [2,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [3,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [4,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [5,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [6,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [7,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [8,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [9,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
> [10,] "1" "2" "A" "B" "1" "2" "A" "B" "1" "2"
>
>
>
> Any help greatly appreciated!
>
> Claudia
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@r-project.org <mailto:R-help@r-project.org> mailing
> list
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> 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 <mailto:R-help@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.
>
>
>
>
> --
> Eloi Mercier
> Bioinformatics PhD Student, UBC
> Paul Pavlidis Lab
> 2185 East Mall
> University of British Columbia
> Vancouver BC V6T1Z4
>
>
--
Eloi Mercier
Bioinformatics PhD Student, UBC
Paul Pavlidis Lab
2185 East Mall
University of British Columbia
Vancouver BC V6T1Z4
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