[R-pkg-devel] query about package design

[ProfJCNash]

I was kind of hoping to avoid reference classes. The optimization stuff
it giving me enough headaches. I've used a local environment
successfully in the Rtnmin package (it is a direct conversion from my
brother's TN Matlab package, which was able to use "globals" there).

JN

On 15-07-10 04:17 PM, Hadley Wickham wrote:
> On Fri, Jul 10, 2015 at 12:50 PM, ProfJCNash <profjcnash at gmail.com> wrote:
>> I have a general question about appropriate design for a fairly
>> complicated package, as I am redesigning and rebuilding the optimx
>> package. It will get a new name as it appears that the calls will change
>> in order to accommodate new functionality. I plan to make it
>> fairly easy to add new optimization (function minimization) tools.
>>
>> The query is whether to use an environment to hold all the common
>> objects (functions, scaled functions, gradients, scaled gradients,
>> hessians, scaled hessians, parameters, scaled parameters, program
>> controls, algorithm tuning parameters, constraints, fixed parametes,
>> some function value history, etc.) The alternative is a set of very
>> long calls, especially when the function needing a quantity may be a
>> couple of layers below the routine that creates or sets the values.
>>
>> The negative side is that the functions are not portable outside the
>> package, so would not be exported.
>>
>> Before I dig into the heavy clay of code that this will need, I thought
>> I should ask if there are issues I might be missing, as the local
>> environment -- essentially "global" variables within the perimeter of
>> the package -- would make the code a lot cleaner, and may offer some
>> useful efficiencies in computation.
> 
> If you want to store the same set of things for many optimisers, you
> might want to consider using reference classes or R6.
> 
> Hadley
>