ronggui wrote:
> The green book tells:"The basic technique is classic :keep it simple
."A long ,complicated expression or function is less fravorable than"
a relatively small computations that combines calls to a few other functions to
perform its tasks."
>
> But I don't get the point totally.Can anyone give me an example to make
me understand this rules totally?
>
> ps:
> Is it mean that f1 is better than f2? Thank you!
>
>
> f1<-function(x){
> n<-length(x)
> s<-sum(x)
> m<-s/n}
>
> f2<-
> function(x){
> m<-sum(x)/length(x)}
No, it means collecting sensible small parts of the code into separate
functions as in
f1 <- function(x, .....){
x1 <- f1a(x, ......)
x2 <- f1b(x1, .....)
x3 <- f1a(x2, .....)
f1c(x1, x2, x3, .....)
}
which is "better" than
f2 <- function(.....){
##
## many lines calculating stuff as in f1a
##
## many lines calculating stuff as in f1b
##
## many lines calculating stuff as in f1a
##
## many lines calculating stuff as in f1c
##
}
Uwe Ligges
>
> 2005-10-23
>
> ------
> Deparment of Sociology
> Fudan University
>
> My new mail addres is ronggui.huang at gmail.com
> Blog:http://sociology.yculblog.com
>
>
>
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