[R] parsing speed

[Jan T. Kim]

On Tue, May 17, 2005 at 09:50:20AM +0200, Martin Maechler wrote:
> >>>>> "BertG" == Berton Gunter <gunter.berton at gene.com>
> >>>>>     on Mon, 16 May 2005 15:20:01 -0700 writes:
> 
>     BertG> (just my additional $.02) ... and as a general rule
>     BertG> (subject to numerous exceptions, caveats, etc.)
> 
>     BertG> 1) it is programming and debugging time that most
>     BertG> impacts "overall" program execution time; 2) this is
>     BertG> most strongly impacted by code readability and size
>     BertG> (the smaller the better); 3) both of which are
>     BertG> enhanced by modular construction and reuseability,
>     BertG> which argues for avoiding inline code and using
>     BertG> separate functions.
> 
>     BertG> These days, i would argue that most of the time it is
>     BertG> program clarity and correctness (they are related)
>     BertG> that is the important issue, not execution speed.
> 
>     BertG> ... again, subject to exceptions and caveats, etc.
> 
> Yes indeed; very good points very well put!
> 
> Just to say it again: 
> 
>  **** We strongly recommend not to "inline" your code, but rather
>  **** program modularly, i.e. call small `utility' functions.

Generally, I fully agree -- modular coding is good, not only in R.
However, with regard to execution time, modularisation that involves
passing of large amounts of data (100 x 1000 data frames etc.) can
cause problems.

Best regards, Jan
-- 
 +- Jan T. Kim -------------------------------------------------------+
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