[R] Logical "and"

[Wiener, Matthew]

Alexander --

a[!(a %in% b)] should do the trick.

setdiff could also probably be used.

Hope this helps,

Matt Wiener

-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Alexander Sokol
Sent: Thursday, November 11, 2004 8:34 AM
To: r-help at stat.math.ethz.ch
Subject: [R] Logical "and"


Hello,

I have the following very simple problem:

Say I have two vectors,

a<-c(1,7,4,5,9,11)
b<-c(7,4,9)

I would like to create a vector containing the elements in a which are not
in 
b.

Obviously, this is possible by writing

a[a!=b[1] & a!=b[2] & a!=b[3]]

But I would like a solution which is applicable to the situation where the 
number of elements in b is unknown.

I have looked in the R manuals, the FAQ and the mailing lists, but have been

unable to find a solution.

Thank you for your replies,
 Alexander

______________________________________________
R-help at stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html