[R] can I rotate a matrix

[Greg Hirson]

Not sure why you are doing it, but you can do it like this:

m = matrix(c(1,3,4,2,2,5,1,6,3), nrow =3)

      [,1] [,2] [,3]
[1,]    1    2    1
[2,]    3    2    6
[3,]    4    5    3


t(m)[ , ncol(m):1]

      [,1] [,2] [,3]
[1,]    4    3    1
[2,]    5    2    2
[3,]    3    6    1

I hope that helps.

Greg

On 3/18/10 12:10 PM, dc896148 wrote:
> useR's,
> I want to be able to rotate a matrix 90 degrees, clockwise.  For example,
>    
>> mat
>>      
>       [,1] [,2] [,3]
> [,1]   1    2     1
> [,2]   3    2     6
> [,3]   4    5     3
>
> I want to rotate it, so that it looks like this...
>       [,1] [,2] [,3]
> [,1]   4    3     1
> [,2]   5    2     2
> [,3]   3    6     1
>
> Does anyone know a quick and straightforward way to do this?
>
> Thanks in advance.
>    

-- 
Greg Hirson
ghirson at ucdavis.edu

Graduate Student
Agricultural and Environmental Chemistry

1106 Robert Mondavi Institute North
One Shields Avenue
Davis, CA 95616