From tplate at blackmesacapital.com  Thu Jun 19 22:21:28 2003
From: tplate at blackmesacapital.com (Tony Plate)
Date: Fri Jun 20 05:21:36 2003
Subject: [Rd] acf   inherits problem
In-Reply-To: <Pine.LNX.4.44.0306190720430.2359-100000@gannet.stats>
References: <029D5E4CC620344D9A54430DABC37F4307B6E3@BOC-EXMAIL1.bocad.bank-banque-canada.ca>
Message-ID: <5.2.1.1.2.20030619103813.042e2e60@mailhost.blackmesacapital.com>

At Thursday 07:45 AM 6/19/2003 +0100, Prof Brian Ripley wrote:
>[...]
>
>The problem is that you have an n x 1 matrix as a time series. That _is_
>somewhat silly, and avoiding that avoids the problem (and it does not
>occur in any of our test suites, unsurprisingly).
>
>I think as.ts/ts ought to drop() such matrices.

Please don't!  Functions that return qualitatively different values (e.g., 
different classes or number of dimensions) depending on input data values 
or lengths of dimensions lead to nasty surprises in automated analyses and 
simulations.  This sort of thing might be nice for interactive use, but it 
makes robust programming difficult.


>[...]
>--
>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

-- Tony Plate


[Rd] acf inherits problem
Tony Plate