[R] new data frame for loop

[Tobias Verbeke]

Hi Emily,

Emily Broccoli wrote:

> I have a data frame with three columns, one coded as a factor. I would like
> to separate my data out into separate data frames according to the factor
> level. Below is a simple example to illustrate. I can get R to return the
> data in the correct format but cannot work out how to get separate data
> frames. I am a newcommer to programming in R so am not sure what I am
> missing! Thanks, Emily
> 
> a<-seq(1,20, by=2)
> b<-seq(1,30, by=3)
> ID<-as.factor(c(1,1,1,2,2,2,3,3,3,3))
> df<-data.frame(a,b,ID)

The function split will give you a list
of data frames split according to a factor:

 > split(df, df$ID)
$`1`
   a b ID
1 1 1  1
2 3 4  1
3 5 7  1

$`2`
    a  b ID
4  7 10  2
5  9 13  2
6 11 16  2

$`3`
     a  b ID
7  13 19  3
8  15 22  3
9  17 25  3
10 19 28  3

See ?split.

HTH,
Tobias

-- 

Tobias Verbeke - Consultant
Business & Decision Benelux
Rue de la révolution 8
1000 Brussels - BELGIUM

+32 499 36 33 15
tobias.verbeke at businessdecision.com