Re: [R] parsing speed

From: Duncan Murdoch <murdoch_at_stats.uwo.ca>
Date: Tue 17 May 2005 - 08:09:14 EST

Federico Calboli wrote:
> Hi everyone,
>
> I have a question on parsing speed.
>
> I have two functions:
>
> F1
> F2
>
> As things are now, F2 calls F1 internally:
>
> F2 = function(x){
> if (something == 1){
> y = F1(x)
> }
> if (something ==2){
> do whatever
> }
> }
>
> *Assuming there could be some difference*, is is faster to use the code
> as written above or should I actually write the statements of F1 to make
> the parsing faster?

The parsing only happens once when you define the functions, and is (almost always) a negligible part of total execution time. I think you're really worried about execution time. You'll probably get more execution time with a separate function because function calls take time.

However, my guess is that putting F1 inline won't make enough difference to notice.

Duncan



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