Bug in the "reformulate" function in stats package

Ben Bolker 
    on Fri, 29 Mar 2019 12:34:50 -0400 writes:

    > I suspect that the issue is addressed (obliquely) in the examples,
    > which shows that variables with spaces in them (or otherwise
    > 'non-syntactic', i.e. not satisfying the constraints of legal R symbols)
    > can be handled by protecting them with backticks  (``)

    > ## using non-syntactic names:
    > reformulate(c("`P/E`", "`% Growth`"), response = as.name("+-"))

    > It seems to me there could be room for a *documentation* patch (stating
    > explicitly that if termlabels has length > 1 its elements are
    > concatenated with "+", and explicitly stating that non-syntactic names
    > must be protected with back-ticks).  (There is a little bit of obscurity
    > in the fact that the elements of termlabels don't have to be
    > syntactically valid names: many will be included in formulas if they can
    > be interpreted as *parseable* expressions, e.g. reformulate("x<2"))

    > I would be happy to give it a shot if the consensus is that it would
    > be worthwhile.

I think it would be worthwhile to add to the docs a bit.

[With currently just your and my vote, we have a 100% consensus
;-)]

Martin

    > One workaround to the OP's problem is below (may be worth including
    > as an example in docs)

    >> z <- c("a variable","another variable")
    >> reformulate(z)

    > Error in parse(text = termtext, keep.source = FALSE) :
    > <text>:1:6: unexpected symbol
    > 1:  ~ a variable
    > ^

    >> reformulate(sprintf("`%s`",z))

    > ~`a variable` + `another variable`

    > On 2019-03-29 11:54 a.m., J C Nash wrote:

    >> The main thing is to post the "small reproducible example".
    >> 
    >> My (rather long term experience) can be written
    >> 
    >> if (exists("reproducible example") ) {
    >> DeveloperFixHappens()
    >> } else {
    >> NULL
    >> }
    >> 
    >> JN
    >> 
    >> On 2019-03-29 11:38 a.m., Saren Tasciyan wrote:

    >>> Well, first I can't sign in bugzilla myself, that is why I wrote here first. Also, I don't know if I have the time at
    >>> the moment to provide tests, multiple examples or more. If that is not ok or welcomed, that is fine, I can come back,
    >>> whenever I have more time to properly report the bug.
    >>> 
    >>> I didn't find the existing bug report, sorry for that.
    >>> 
    >>> Yes, it is related. My problem was that I have column names with spaces and current solution doesn't solve it. I have a
    >>> solution, which works for me and maybe also for others.
    >>> 
    >>> Either, someone can register me to bugzilla or I can post it here, which could give some direction to developers. I
    >>> don't mind whichever is preferred here.
    >>> 
    >>> Best,
    >>> 
    >>> Saren
    >>> 
    >>> 
    >>> On 29.03.19 09:29, Martin Maechler wrote:

    >>>>>>>>> Saren Tasciyan
    >>>>>>>>> ???? on Thu, 28 Mar 2019 17:02:10 +0100 writes:

    >>>> ???? > Hi,
    >>>> ???? > I have found a bug in reformulate function and have a solution for it. I
    >>>> ???? > was wondering, where I can submit it?
    >>>> 
    >>>> ???? > Best,
    >>>> ???? > Saren
    >>>> 
    >>>> 
    >>>> Well, you could have given a small reproducible example
    >>>> depicting the bug, notably when posting here:
    >>>> Just a prose text with no R code or other technical content is
    >>>> almost always not really appropriate fo the R-devel mailing list.
    >>>> 
    >>>> Further, in such a case you should google a bit and hopefully
    >>>> have found
    >>>> ??????? https://www.r-project.org/bugs.html
    >>>> 
    >>>> which also mention reproducibility (and many more useful things).
    >>>> 
    >>>> Then it also tells you about R's bug repository, also called
    >>>> "R's bugzilla" at https://bugs.r-project.org/
    >>>> 
    >>>> and if you are diligent (but here, I'd say bugzilla is
    >>>> (configured?) far from ideal), you'd also find bug PR#17359
    >>>> 
    >>>> ??? https://bugs.r-project.org/bugzilla/show_bug.cgi?id=17359
    >>>> 
    >>>> which was reported already on Nov 2017 .. and only fixed
    >>>> yesterday (in the "cleanup old bugs" process that happens
    >>>> often before the big new spring release of R).
    >>>> 
    >>>> So is your bug the same as that one?
    >>>> 
    >>>> Martin
    >>>> 
    >>>> ???? > --
    >>>> ???? > Saren Tasciyan
    >>>> ???? > /PhD Student / Sixt Group/
    >>>> ???? > Institute of Science and Technology Austria
    >>>> ???? > Am Campus 1
    >>>> ???? > 3400 Klosterneuburg, Austria
    >>>> 
    >>>> ???? > ______________________________________________
    >>>> ???? > R-devel at r-project.org mailing list
    >>>> ???? > https://stat.ethz.ch/mailman/listinfo/r-devel
    >>>> 
    >>>> ______________________________________________
    >>>> R-devel at r-project.org mailing list
    >>>> https://stat.ethz.ch/mailman/listinfo/r-devel

    >> 
    >> ______________________________________________
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    >> 

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