[Rd] as.data.frame.character lacks nm= argument

peter dalgaard pdalgd at gmail.com
Fri Sep 14 17:10:48 CEST 2012


On Sep 14, 2012, at 15:25 , Prof Brian Ripley wrote:

> On 13/09/2012 21:48, Bert Gunter wrote:
>> Bill:
>> 
>> as.data.frame.character() has no nm, argument, so providing one causes
>> the error as you can see from the code. Presumably, this is what you
>> meant by bug/inconsistency, right?
> 
> This is using an undocumented argument, 'nm'.  I don't believe anything is said about what might happen if you do that except that it will be passed to methods -- they are not obliged to accept it.
> 
> If it were intended for this to be a feature, I think the author might have chosen a less opaque name than 'nm'.

It wasn't, but the author (me) might have chosen a _more_ opaque name if he had thought it necessary to keep people from using undocumented arguments. As it happened, I think I just promoted a variable name inside as.data.frame.vector to become an argument.

But it was a long time ago, in a different job, and besides....

> 
> Where we go from here is under discussion in R-core.
> 
>> 
>> -- Bert
>> 
>> On Thu, Sep 13, 2012 at 1:32 PM, William Dunlap <wdunlap at tibco.com> wrote:
>>> Is the following behavior with as.data.frame(nm=...) a bug?  It is an inconsistency:
>>> 
>>>> as.data.frame(LETTERS[1:10], nm="FirstTenLetters")
>>> Error in as.data.frame.vector(x, ..., nm = nm) :
>>>   formal argument "nm" matched by multiple actual arguments
>>> 
>>> nm= works for integer arguments:
>>> 
>>>> as.data.frame(1:10, nm="OneToTen")
>>>    OneToTen
>>> 1         1
>>> 2         2
>>> 3         3
>>> 4         4
>>> 5         5
>>> 6         6
>>> 7         7
>>> 8         8
>>> 9         9
>>> 10       10
>>> 
>>> Bill Dunlap
>>> Spotfire, TIBCO Software
>>> wdunlap tibco.com
>>> 
>>> ______________________________________________
>>> R-devel at r-project.org mailing list
>>> https://stat.ethz.ch/mailman/listinfo/r-devel
>> 
>> 
>> 
> 
> 
> -- 
> Brian D. Ripley,                  ripley at stats.ox.ac.uk
> Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
> University of Oxford,             Tel:  +44 1865 272861 (self)
> 1 South Parks Road,                     +44 1865 272866 (PA)
> Oxford OX1 3TG, UK                Fax:  +44 1865 272595
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel

-- 
Peter Dalgaard, Professor
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com



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