From murdoch at stats.uwo.ca  Tue Aug  7 12:33:47 2007
From: murdoch at stats.uwo.ca (Duncan Murdoch)
Date: Tue, 07 Aug 2007 06:33:47 -0400
Subject: [Rd] Optimization in R
In-Reply-To: <20070807031813.GA1530@ms.unimelb.edu.au>
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Message-ID: <46B84A8B.1070601@stats.uwo.ca>

Those are small parts of the calculation, not the whole thing.  The 
original point was that optim() is a very thin wrapper around the code 
to do the optimization.  I just don't see a need to make it more 
complicated so it can be used to wrap other methods.  Authors of new 
optimization methods can just create new functions, following the 
pattern set by optim(), and it will be easier for almost everyone.

Duncan Murdoch

On 06/08/2007 11:18 PM, Andrew Robinson wrote:
>  ... Variance and correlation model classes in nlme.
> 
> Cheers
> 
> Andrew
> 
> On Mon, Aug 06, 2007 at 09:55:38PM -0500, hadley wickham wrote:
>> On 8/4/07, Duncan Murdoch <murdoch at stats.uwo.ca> wrote:
>>> On 04/08/2007 2:53 PM, Gabor Grothendieck wrote:
>>>> The example of generic functions.
>>> Show me an example where we have a list of ways to do a calculation
>>> passed as an argument (analogous to the method argument of optim), where
>>> the user is allowed to add his own function to the list.
>> Bin width selection in hist?  Family functions for glm?  Those come
>> quickly to my mind, but I'm sure there are others.
>>
>> Hadley
>>
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel
>



[Rd] Optimization in R
Duncan Murdoch