[R] R-how to group the data

[Sean Davis]

On 12/9/05 7:19 AM, "Subhabrata" <subhabratapal at sraindia.com> wrote:

> 
> Hello R - users,
> 
> This may sound simple to may people:
> 
> I have a list of data as follows
> 
>      type value
>       y 7
>       y 7
>       y 8
>       y 8
>       y 8
>       y 9
>       y 9
>       y 9
>       y 9
>       y 10
>       y 10
>       y 10
>       y 10
>       y 11
>       y 11
>       y 12
>       y 12
>       y 14
>       y 14
>       y 14
>       y 15
>       y 17
>       y 20
>       y 20
>       y 20
>       y 20
>       y 25
>       y 25
>       y 25
>       x 7
>       x 7
>       x 8
>       x 8
>       x 9
>       x 9
>       x 11
>       x 11
>       x 11
>       x 12
>       x 12
>       x 12
>       x 13
>       x 13
>       x 15
>       x 15
>       x 15
>       x 18
>       x 20
>       x 30
>       x 30
> 
> Is there any way where I can group all the x and y like
> 
> a <- all the values of x
> b <- all the values of y
> 
> so 'a' will  have = 7, 7, 8....
>     'b' = 7,7,8,8,8...

Look at ?split.

 vec <- c(1,2,3,4,5,10,11,12,13,14,15,16)
 myletters <- c(rep('a',5),rep('b',7))
 mylist <- split(vec,myletters)
 mylist$a
 mylist$b

Sean