Re: Compare two vectors without a loop

[Sundar Dorai-Raj <sundar.dorai-raj@pdf.com>]

yiwu ye wrote:
> Dear list members,
>  
> suppose I have:
> x y
> 1 3
> 2 4
> 3 5
> 4 6
> 5 6
> I want to make a comparison between x and y, and to produce a new vector 
> like
> z
> T
> T
> T
> F
> F
> so, I can know the first three elements of y, 3,4,5,can find the same 
> value in x.
> Could someone told how I can do it without a loop, please? Many thanks.
>  
> Yiwu
In S-PLUS 6.1 just use the %in% operator:

z <- y %in% x

In older versions of S-PLUS, library(hmisc) has the %in% operator or 
just use ?match.
Regards,
Sundar