Message-ID: <16559.13998.438223.381658@bossiaea.maths.uwa.edu.au>
Date: 2004-05-22T13:17:15Z
From: Berwin A Turlach
Subject: Buglet/omission in nls package (PR#6901)
In-Reply-To: <Pine.LNX.4.44.0405221137001.12669-100000@gannet.stats>
G'day Brian,
>>>>> "BDR" == Prof Brian Ripley <ripley@stats.ox.ac.uk> writes:
BDR> No one has said the coef() will work on a summary object,
But no one said that coef() will not work on a summary object either. :)
BDR> but it would be nice if it did where appropriate.
Agreed, I looked up the help page and I think it is a bit ambiguous
about this point. It starts off with:
Description:
'coef' is a generic function which extracts model coefficients
from objects returned by modeling functions. [...]
O.k., summary functions are not modeling functions, so one can argue
that one cannot expect coef() to work on summary objects. But then
the help page continues and says:
Arguments:
object: an object for which the extraction of model coefficients is
meaningful.
And I would argue that the extraction of model coefficients is indeed
meaningful for objects of class "summary.lm", "summary.nls",
"summary.glm" and probably a few others too. :)
OTOH, extracting model coefficient from an object of class
"summary.aov" is probably not meaningful....
BDR> I've added an summary.nls method for 2.0.0.
Thanks!
Cheers,
Berwin