[Year 12 SofDev] A matter of style - GUI data structures vs primitives

[Mark KELLY]

On 29 November 2010 10:54, Steven Bird <sb at csse.unimelb.edu.au> wrote:

> On 29 November 2010 10:38, Mark KELLY <kel at mckinnonsc.vic.edu.au> wrote:
> > Most programming languages now offer GUI data structures like listboxes,
> > grids etc.
> > I'm interested to know how many people use them as their primary data
> > structures ...
>
> Are you talking about how you use the graphical interface of the IDE
> that comes with your favourite programming language, or are you
> talking about the API to the graphics library that comes with the
> language?
>

Yes - the IDE's GUI controls (listboxes, grids, combo boxes etc)


> > What sort of performance penalty does the use of the GUI data structure
> > impose? Do the GUI structure's capabilities (e.g. auto-sorting lists)
> > outweigh the penalty?
> > How efficient is the GUI's inbuilt sorting algorithm compared to a good
> > do-it-yourself sorting algorithm?
>
> A built-in sorting function will usually be close to the optimal O(n
> log n) performance.   If you implement your own (by why would you
> these days?) then it might be as bad as O(n^2).  However, the
> difference between these is likely to be insignificant for the size of
> data you're talking about.  The dominant factor might be that the
> built-in function was compiled, while yours might be interpreted (if
> you're using VB, PHP, Python, etc).
>

Yes, 1000 guys at Microsoft would probably beat me in an algorithm contest.
;-)
But if you have a large array and you need to sort it, you need to sort it.
You either write your own sort routine, or toss the data into a pre-packaged
object and use its methods to do the job for you.

I was more interested in the performance differences between using a listbox
(say) rather than an array.
I'm guessing it's like lazily choosing 'variant' in VB instead of carefully
crafting your variable types and your explicit typecasts.

I sometimes duplicate data in an array (for processing) and a GUI structure
(e.g. a listbox) for display and data entry. Programming (for me at least)
is usually a private, solo activity and there is not a lot of opportunity to
see how other people do things, so I was interested in how other people
choose to use primitive and GUI alternative data structures if both are
available.

Cheers
Mark



>
> -Steven Bird
> http://www.csse.unimelb.edu.au/~sb/<http://www.csse.unimelb.edu.au/%7Esb/>
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-- 
Mark Kelly
Manager Information Systems
Reporting Manager
IT Learning Area Manager

McKinnon Secondary College
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Victoria, Australia
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kel at mckinnonsc.vic.edu.au

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