From ripley at stats.ox.ac.uk  Tue Sep 19 15:15:51 2006
From: ripley at stats.ox.ac.uk (Prof Brian Ripley)
Date: Tue, 19 Sep 2006 14:15:51 +0100 (BST)
Subject: [Rd] Help for methods
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On Tue, 19 Sep 2006, hadley wickham wrote:

>> > Well, I know that, and you know that, but how is anyone supposed to
>> > figure it out?  It means that you need to have a working knowledge of
>> > the S3 and S4 class systems before you can use the help to reliably
>> > get the documentation you need.
>> 
>> For S3 you do to understand that there are different methods, and it
>> is in `An Introduction to R'.  And ?summary reminds you.
>
> But you also have to be able to identify if it is a S3 function or an
> S4 method (or an ordinary function).

Why not just type ?summary, which as I said, does tell you up front?

> The reason I find this so much of a problem is that when you are
> teaching R, one of the first things you want to do is teach your
> students how to use help.  However, you can't teach them to use it
> effectively until they know an awful lot about how the call semantics
> of R.

In many years of teaching S/R I have not found that to be a problem.

-- 
Brian D. Ripley,                  ripley at 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




[Rd] Help for methods
Prof Brian Ripley