On 29 Nov 2006 at 12:08, Peter Dalgaard wrote:

Date sent:              Wed, 29 Nov 2006 12:08:21 +0100
From:                   Peter Dalgaard <[EMAIL PROTECTED]>
To:                     Wolfram Fischer <[EMAIL PROTECTED]>
Copies to:              r-help@stat.math.ethz.ch
Subject:                Re: [R] Why the factor levels returned by cut() are not 
ordered?

> Wolfram Fischer wrote:
> > What is the reason, that the levels of the factor
> > returned by cut() are not marked as ordered levels?
> >
> >   
> >> is.ordered( cut( breaks=3, sample(10 ) ) )
> >>     
> > FALSE
> >
> >   
> It would arguably be the Right Thing, but there would be complications
> in modeling, where ordered factors result in polynomial contrast
> coding. (This, in my opinion, is a design mistake inherited from S,
> but it's not easy to change at this stage.)

Well

what about to change cut.default

 if (codes.only)
         code
     else factor(code, seq(labels), labels)

to

 if (codes.only)
         code
     else factor(code, seq(labels), labels, ...)

which enables to use ordered switch

> is.ordered( cut( breaks=3, sample(10 ), ordered=T ) )
[1] TRUE

Without this the result is same as before (I believe :-)

Petr

 >> help(factor) >>     >  
>   ... >     If 'ordered' is 'TRUE', the factor levels are assumed to
> be ordered. >     ... > > Wolfram > >
> ______________________________________________ >
> R-help@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 > and
> provide commented, minimal, self-contained, reproducible code. >   
> 
> 
> -- 
>    O__  ---- Peter Dalgaard             Řster Farimagsgade 5, Entr.B
>   c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
>  (*) \(*) -- University of Copenhagen   Denmark          Ph:  (+45)
>  35327918
> ~~~~~~~~~~ - ([EMAIL PROTECTED])                  FAX: (+45)
> 35327907
> 
> ______________________________________________
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> PLEASE do read the posting guide
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Petr Pikal
[EMAIL PROTECTED]

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