[R] determine frequencies in a matrix by row

[jim holtman]

If the result is limited to just the counts of 1,2 and 3, you can do
the following:

> habs <- matrix(sample(1:3, 50, TRUE, prob=c(.6,.2,.2)),5,10)
> habs
     [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,]    1    3    2    1    1    3    1    1    1     2
[2,]    1    2    3    1    3    1    1    1    1     1
[3,]    1    2    3    2    3    1    2    1    1     3
[4,]    3    1    3    1    2    2    1    1    1     2
[5,]    1    1    2    2    1    1    3    1    3     2
> result <- apply(habs, 1, function(x){
+     c('1' = sum(x == 1), '2' = sum(x==2), '3' = sum(x == 3))
+ })
> cbind(habs, t(result))
                         1 2 3
[1,] 1 3 2 1 1 3 1 1 1 2 6 2 2
[2,] 1 2 3 1 3 1 1 1 1 1 7 1 2
[3,] 1 2 3 2 3 1 2 1 1 3 4 3 3
[4,] 3 1 3 1 2 2 1 1 1 2 5 3 2
[5,] 1 1 2 2 1 1 3 1 3 2 5 3 2


On Wed, Jun 8, 2011 at 2:23 AM, the_big_kowalski <bkowalski at csumb.edu> wrote:
> Hi,
>
> I have a matrix
>     [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
> [1,]    1    3    1    1    3    1    1    2    3     2
> [2,]    1    3    1    2    1    1    1    2    2     1
> [3,]    1    2    2    3    2    1    1    1    2     1
> [4,]    3    2    1    1    1    3    1    2    1     2
> [5,]    1    1    2    2    1    1    3    1    1     2
> and want to determine how many times 1s, 2s, and 3s occur per each row.
> I tried using 'table', but end up with frequencies for the whole matrix.
> Thanks in advance for your help
>
> --
> View this message in context: http://r.789695.n4.nabble.com/determine-frequencies-in-a-matrix-by-row-tp3581733p3581733.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
Data Munger Guru

What is the problem that you are trying to solve?