[R] names.data.frame?

[Rui Barradas]

Hello,

I too would expected NextMethod to work but the following seems to be 
simpler.
"names" is an attribute, so should be accessible with attr.



names.pm = function(p) {
   attr(p, "names")
}

p = data.frame(x=1:3, coeff=1)
class(p) = c("pm", class(p));

names(p)
#[1] "x"     "coeff"



Hope this helps,

Rui Barradas

Às 18:35 de 03/11/21, Leonard Mada via R-help escreveu:
> Dear List members,
> 
> 
> Is there a way to access the default names() function?
> 
> 
> I tried the following:
> 
> # Multi-variable polynomial
> 
> p = data.frame(x=1:3, coeff=1)
> 
> class(p) = c("pm", class(p));
> 
> 
> names.pm = function(p) {
> # .Primitive("names")(p) # does NOT function
> # .Internal("names")(p) # does NOT function
> # nms = names.default(p) # does NOT exist
> # nms = names.data.frame(p) # does NOT exist
> # nms = names(p); # obvious infinite recursion;
> nms = names(unclass(p));
> }
> 
> 
> Alternatively:
> 
> Would it be better to use dimnames.pm instead of names.pm?
> 
> I am not fully aware of the advantages and disadvantages of dimnames vs 
> names.
> 
> 
> Sincerely,
> 
> 
> Leonard
> 
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