From sdorairaj at gmail.com  Thu Jul 30 23:30:27 2009
From: sdorairaj at gmail.com (Sundar Dorai-Raj)
Date: Thu, 30 Jul 2009 14:30:27 -0700
Subject: [Rd] update.formula and backticked colons
In-Reply-To: <c9ce82b00907301428y698e401by2c3334b41ff7fc4c@mail.gmail.com>
References: <c9ce82b00907301428y698e401by2c3334b41ff7fc4c@mail.gmail.com>
Message-ID: <c9ce82b00907301430p1186243eq7f79cb503d8919ae@mail.gmail.com>

On Thu, Jul 30, 2009 at 2:28 PM, Sundar Dorai-Raj<sdorairaj at gmail.com> wrote:
> I just noticed the following in update.formula and I'm wondering if
> this behavior is the intention of the developers. Here's an example:
>
> update(`a: b` ~ x, ~ . + y)
>
> Note now that the response has no backticks and is interpreted as a:b
> (i.e. ":" is now an operator). This is because in update.formula the
> call to terms.formula uses simplify = TRUE. I'm working with data that
> has a lot of colons in their names and for reporting purposes I don't
> want to use make.names to avoid this situation. I do have a solution
> which simply avoids using update.formula, but I wonder if the
> developers would consider removing the "simplify" argument and allow
> it to be passed through "...", which is currently ignored by
> update.formula. Alternatively, add a simplify=TRUE to the
> update.formula call, which can manually be set to FALSE by the user.
>
> I would love to hear any comments or criticisms of my findings.
>
> Thanks,
>
> --sundar
>

Forgot my version info

> version
               _
platform       x86_64-unknown-linux-gnu
arch           x86_64
os             linux-gnu
system         x86_64, linux-gnu
status
major          2
minor          9.1
year           2009
month          06
day            26
svn rev        48839
language       R
version.string R version 2.9.1 (2009-06-26)



[Rd] update.formula and backticked colons
Sundar Dorai-Raj