[R] split data set

[Aimin Yan]

I have a data(ABC) like this:

      x   y
A   3   4
A   1   3
B   2   6
B   4   8
C   5   4
C   6   7

I want to split this data into

A:
   x   y
A   3   4
A   1   3

B
B   2   6
B   4   8

C
C   5   4
C   6   7

anyone knows how to do that?

thanks,

Aimin Yan