Or:

combn(1:4, 2, paste, collapse = ' and ')

On Tue, May 11, 2010 at 5:54 PM, Ista Zahn <istazahn@gmail.com> wrote:

> On Tuesday 11 May 2010 4:27:01 pm David Winsemius wrote:
> > On May 11, 2010, at 1:45 PM, chen jia wrote:
> > > Hi there,
> > >
> > > I am looking for a function that takes a vector as input and generates
> > > all pair wise combination of the elements of the input vector.
> >
> > ?combn
> >
> > > For example, the input vector is c(1,2,3,4). The output vector is c(1
> > > and 2, 1 and 3, 1 and 4, 2 and 3, 2 and 4, 3 and 4).
> >
> > That's not a vector.
>
> True, although it is possible the OP wanted paste(combn(1:4, 2)[1,], "and",
> combn(1:4, 2)[2,])
>
> -Ista
>
> >
> > > The
> > > representation here is generic.
> > >
> > > I can use a for loop to do it, but it gets slow when the number of
> > > elements of the input vector is large.
> > >
> > > Best,
> > > Jia
> >
> > David Winsemius, MD
> > West Hartford, CT
> >
> > ______________________________________________
> > R-help@r-project.org mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide
> > http://www.R-project.org/posting-guide.html and provide commented,
> > minimal, self-contained, reproducible code.
>
> ______________________________________________
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>



-- 
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40" S 49° 16' 22" O

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