On Wed, Jun 08, 2011 at 08:35:34PM -0400, Simon Urbanek wrote:
>
> On Jun 8, 2011, at 8:32 PM, oliver wrote:
>
> > On Thu, Jun 09, 2011 at 02:17:31AM +0200, oliver wrote:
> > [...]
> >> OK, I looked at this now.
> >>
> >> LENGTH() checks the length of the vector.
> >>
> >> Good to know this.
> >>
> >> So the problem of a vector of length 0 can be with any arguments of type
> >> SEXP,
> >> hence I will need to check ANY arg on it's length.
> >>
> >> This is vital to stability under any situation.
> >>
> >> Thanks for this valuable hint!
> >>
> >> I will add checks for all my SEXP-args.
> > [...]
> >
> > Hey, LENGTH() does not work with String-vectors! :(
> >
>
> Of course it does ...
>
>
It does not so on my R 2.10.1 installation.
In the R-Shell I get:
==============================
> length(c())
[1] 0
>
==============================
So c() is vec of length 0.
When I feed my readjpeg() with c() as filename arg,
testing with:
====================================================
if( LENGTH( filename_sexp ) < 1 )
{
error("LENGTH( filename_sexp ) < 1");
//error("filename can't be vector of length 0");
}
else
{
error("LENGTH( filename_sexp ) is not < 1");
}
====================================================
I got:
Error in readjpeg(filename = c()) : LENGTH( filename_sexp ) is not < 1
You can explain why?
Ciao,
Oliver
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