[R] Initialize many variables to NUL, check whether an object exist

[Gabor Csardi]

What is RG? I suspect it is not a list but a vector and 
you operation you wrote does not make sense. Convert it 
to a list if you want to store c("a","b") is RG[["AB"]].

G.

On Tue, Apr 15, 2008 at 12:06:14AM +0800, Ng Stanley wrote:
> Hi,
> 
> How can I force the assignment ?
> 
> > RG[["ABC"]] <- c("a", "b")
> Error in RG[["ABC"]] <- c("a", "b") :
>   more elements supplied than there are to replace
> 
> 
> On Mon, Apr 14, 2008 at 9:53 PM, Gabor Csardi <csardi at rmki.kfki.hu> wrote:
> 
> > On Mon, Apr 14, 2008 at 09:47:49PM +0800, Ng Stanley wrote:
> > > Hi,
> > >
> > > Two questions:
> > >
> > > A) I need to initialize many variables to NULL. So I created
> > variable_names
> > > <- c("a1", "a2"). What can I do to variable_names so that variable a1 is
> > > NULL and a2 is NULL ?
> >
> > for (n in variable_names) assign(n, NULL)
> >
> > > B) How can I check whether an object exist ?
> >
> > help.search("exists")
> >
> > G.
> >
> > > Thanks
> > > Stanley
> > >
> > >       [[alternative HTML version deleted]]
> > >
> > > ______________________________________________
> > > R-help at 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<http://www.r-project.org/posting-guide.html>
> > > and provide commented, minimal, self-contained, reproducible code.
> >
> > --
> > Csardi Gabor <csardi at rmki.kfki.hu>    UNIL DGM
> >
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at 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.

-- 
Csardi Gabor <csardi at rmki.kfki.hu>    UNIL DGM