[R] Assessing the name of an object within an argument

[Bert Gunter]

This is false. formals() gives the FORMAL argument list of the function,
not the ACTUAL arguments supplied. That is obtained by the construction

deparse(substitute(dataset))

The OP should consult a good R tutorial for this and other uses of
substitute(), part of the "computing on the language" functionality of R.

Bert



On Jan 10, 2017 4:04 AM, "Thomas Mailund" <mailund at birc.au.dk> wrote:


You can get that using `formals()`.

my_func <- function(dataset = iris)
{
  #print(dataset) # here I do not want to print the dataset but the name
  # of the object - iris in this case - instead

  print(formals()$dataset) # this is what you want
}

This gives you what the arguments were as an alist. It won’t always be a
name, of course, but when it is, as in this case, that will be a symbol you
can print.

Cheers
        Thomas



On 10 January 2017 at 09:51:55, g.maubach at weinwolf.de (g.maubach at weinwolf.de
(mailto:g.maubach at weinwolf.de)) wrote:

> Hi All,
>
> I have a function like
>
> my_func <- function(dataset)
> {
> some operation
> }
>
> Now I would like not only to operate on the dataset (how this is done is
> obvious) but I would like to get the name of the dataset handed over as an
> argument.
>
> Example:
>
> my_func <- function(dataset = iris)
> {
> print(dataset) # here I do not want to print the dataset but the name
> of the object - iris in this case - instead
> # quote() does not do the trick cause it prints "dataset" instead of
> "iris"
> # as.name() gives an error saying that the object can not coerced to a
> symbol
> }
>
> Is there a way to do this?
>
> Kind regards
>
> Georg
>
> ______________________________________________
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posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
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