[R] Romoving elements from a vector. Looking for the opposite of c(), New user

[Charilaos Skiadas]

On Nov 15, 2007, at 9:15 AM, Thomas Frööjd wrote:

> Hi
>
> I have three vectors say x, y, z. One of them, x contains observations
> on a variable. To x I want to append all observations from y and
> remove all from z. For appending c() is easily used
>
> x <- c(x,y)
>
> But how do I remove all observations in z from x? You can say I am
> looking for the opposite of c().

If you are looking for the opposite of c, provided you want to remove  
the first part of things, then perhaps this would work:

z<-c(x,y)
z[-(1:length(x))]

However, if you wanted to remove all appearances of elements of x  
from c(x,y), regardless of whether those elements appear in the x  
part of in the y part, I think you would want:

z[!z %in% x]

Probably there are other ways.

Welcome to R!

> Best regards

Haris Skiadas
Department of Mathematics and Computer Science
Hanover College