Message-ID: <644e1f320904171019l6cfa66d6j76f8e2a2ee6d7513@mail.gmail.com>
Date: 2009-04-17T17:19:07Z
From: jim holtman
Subject: numbers loop in R
In-Reply-To: <23099591.post@talk.nabble.com>
try this:
> matrixx<-function(A){
+ B=matrix(NaN,nrow=(A+1),ncol=4)
+ k <- 1
+ for (i in 3:A){
+ for (j in i:A) {
+ B[k,] <- c(NaN, i-2, i-1, j)
+ k <- k + 1
+ }
+ }
+ B
+ }
> matrixx(5)
[,1] [,2] [,3] [,4]
[1,] NaN 1 2 3
[2,] NaN 1 2 4
[3,] NaN 1 2 5
[4,] NaN 2 3 4
[5,] NaN 2 3 5
[6,] NaN 3 4 5
>
On Fri, Apr 17, 2009 at 11:11 AM, emj83 <stp08emj at shef.ac.uk> wrote:
>
> I would like to create a matrix in R that looks similar to this:
>
> ? ? [,1] [,2] [,3] [,4]
> [1,] ?NaN ?1 ?2 ?3
> [2,] ?NaN ?1 ?2 ?4
> [3,] ?NaN ? 1 ?2 ?5
> [4,] ?NaN ?2 ?3 ?4
> [5,] ?NaN ?2 ?3 ?5
> [6,] ?NaN ? ?3 ? ?4 ? ?5
>
> I have the loop below:
>
> where A for example is 5
>
> matrixx<-function(A){
> B=matrix(NaN,nrow=(A+1),ncol=4)
> ? ? ? ?for(k in 1:(A+1)){
> ? ? ? ? ? ? ? ?for(i in 1:(A-2)){
> ? ? ? ? ? ? ? ? ? ? for(j in (i+2):A){
> ? ? ? ? ? ? ? ? ? ? }
> ? ? ? ? ? ? ? ?}
> ? ? ? }
> B[k,]=c(NaN,i,(i+1),j)
> print(B)
> }
>
> But it only prints the final line in:
>
>> matrixx(5)
> ? ? [,1] [,2] [,3] [,4]
> [1,] ?NaN ?NaN ?NaN ?NaN
> [2,] ?NaN ?NaN ?NaN ?NaN
> [3,] ?NaN ?NaN ?NaN ?NaN
> [4,] ?NaN ?NaN ?NaN ?NaN
> [5,] ?NaN ?NaN ?NaN ?NaN
> [6,] ?NaN ? ?3 ? ?4 ? ?5
>
> Could anyone give me a hand? Would be much appreciated.
>
> Thanks Emma
>
> --
> View this message in context: http://www.nabble.com/numbers-loop-in-R-tp23099591p23099591.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> 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.
>
--
Jim Holtman
Cincinnati, OH
+1 513 646 9390
What is the problem that you are trying to solve?