R help - Jan 2007 - Permutation problem

Dear R-Users,

I need a matrix containing line by line all possible permutations with
length 'i'  of the integers 1:N, given the restriction that the
integers in each row have to be in ascending order.

For example: N = 5, length i = 3, should result in a matrix like this:
1  2  3
1  2  4
1  2  5
1  3  4
1  3  5
1  4  5
2  3  4
2  3  5
2  4  5
3  4  5

I'm grateful for any advice on how to proceed,
  Michel Lang

> help.search('combination')
> ?combn
> combn(1:5,3)
     [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,]    1    1    1    1    1    1    2    2    2     3
[2,]    2    2    2    3    3    4    3    3    4     4
[3,]    3    4    5    4    5    5    4    5    5     5
>
On 1/30/07, michel lang <michellang at gmail.com>
wrote:
> Dear R-Users,
>
> I need a matrix containing line by line all possible permutations with
> length 'i'  of the integers 1:N, given the restriction that the
> integers in each row have to be in ascending order.
>
> For example: N = 5, length i = 3, should result in a matrix like this:
> 1  2  3
> 1  2  4
> 1  2  5
> 1  3  4
> 1  3  5
> 1  4  5
> 2  3  4
> 2  3  5
> 2  4  5
> 3  4  5
>
> I'm grateful for any advice on how to proceed,
>  Michel Lang
>
> ______________________________________________
> R-help at stat.math.ethz.ch 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 you are trying to solve?

Hi


 > library(gtools)
 > combinations(5,3)
       [,1] [,2] [,3]
[1,]    1    2    3
[2,]    1    2    4
[3,]    1    2    5
[4,]    1    3    4
[5,]    1    3    5
[6,]    1    4    5
[7,]    2    3    4
[8,]    2    3    5
[9,]    2    4    5
[10,]    3    4    5
 >






On 30 Jan 2007, at 12:22, michel lang wrote:
> Dear R-Users,
>
> I need a matrix containing line by line all possible permutations with
> length 'i'  of the integers 1:N, given the restriction that the
> integers in each row have to be in ascending order.
>
> For example: N = 5, length i = 3, should result in a matrix like this:
> 1  2  3
> 1  2  4
> 1  2  5
> 1  3  4
> 1  3  5
> 1  4  5
> 2  3  4
> 2  3  5
> 2  4  5
> 3  4  5
>
> I'm grateful for any advice on how to proceed,
>   Michel Lang
>
> ______________________________________________
> R-help at stat.math.ethz.ch 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.
--
Robin Hankin
Uncertainty Analyst
National Oceanography Centre, Southampton
European Way, Southampton SO14 3ZH, UK
  tel  023-8059-7743