[R] Why does a custom function called is.numeric.factor break lattice?

Bert Gunter bgunter.4567 at gmail.com
Mon Nov 16 17:21:09 CET 2015


Thanks Duncan. You are right; I missed this.

Namespaces and full qualification seems the only reliable solution to
the general issue though -- right?

Cheers,
Bert





Bert Gunter

"Data is not information. Information is not knowledge. And knowledge
is certainly not wisdom."
   -- Clifford Stoll


On Mon, Nov 16, 2015 at 7:42 AM, Duncan Murdoch
<murdoch.duncan at gmail.com> wrote:
> On 16/11/2015 10:22 AM, Bert Gunter wrote:
>>
>> There is no multiple dispatch; just multiple misunderstanding.
>>
>> The generic function is "is.numeric" . Your method for factors is
>> "is.numeric.factor".
>>
>> You need to re-study.
>
>
>
> I think the problem is with S3.  "is.numeric.factor" could be a
> "numeric.factor" method for the "is" generic, or a "factor" method for the
> "is.numeric" generic.  Using names with dots is a bad idea. This would be
> all be simpler and less ambiguous if the class had been named
> "numeric_factor" or "numericFactor" or anything without a dot.
>
> Duncan Murdoch



More information about the R-help mailing list