Message-ID: <Pine.LNX.4.44.0307230843350.26690-100000@gannet.stats>
Date: 2003-07-23T09:47:00Z
From: Brian Ripley
Subject: abs() and negative output from fractions() (PR#3536)
In-Reply-To: <e8nrhvoon75dsu40ibcv9rc8cqnuk9r345@4ax.com>
On Tue, 22 Jul 2003, Duncan Murdoch wrote:
> On Wed, 23 Jul 2003 00:49:05 +0200 (MET DST), you wrote:
>
> >Hi,
> >
> >zeros is output from fractions()
> >
> >>zeros
> >[1] -2 -2/5 1 4/3
> >>abs(zeros)
> >[1] -2 -2/5 1 4/3
>
> The fractions() function is presumably the one from MASS; questions
> about contributed packages (even recommended ones) should go to the
> package maintainer. They are not R bugs.
This is not even a VR bug: no one said abs() is implemented for fractions,
and it is not. From the help page:
Arithmetic operations on `"fractions"' objects are possible.
and abs() is not such an operation.
--
Brian D. Ripley, ripley@stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
Oxford OX1 3TG, UK Fax: +44 1865 272595