[R] data manipulation

[Dieter Menne]

Marc Bernard <bernarduse1 <at> yahoo.fr> writes:

> I would be grateful if you can help me. My problem is the following:
> I have a data set like:
> 
> ID  time      X1          X2
> 1    1          x111      x211
> 1    2          x112      x212
....
 
> where X1 and X2 are 2 covariates and "time" is the time of observation and ID 
indicates the cluster.
> 
> I want to merge the above data by creating a new variable  "X" and "type" as 
follows:
> 
> ID   time    X            type
> 1     1      x111         X1
....

Try reshape. And have courage, this is one of the more complex interfaces in R, 
very powerful, but intimidating.

Dieter