Message-ID: <Pine.SGI.4.40.0411110929180.51600905-100000@origin.chass.utoronto.ca>
Date: 2004-11-11T14:31:02Z
From: Jean Eid
Subject: Logical "and"
In-Reply-To: <41B2867D@webmail2.ofir.dk>
You can use setdiff if you only need the unique values of a that are not
in b. If you want all values you can use
a[a%in%setdiff(a,b)]
There are also intersection, union etc...
see
?setdiff
On Thu, 11 Nov 2004, Alexander Sokol wrote:
> 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
>
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