Hi
You definitely shall consult an introduction manuals you can find in
doc directory of your R installation. Good starting point is also
http://www.r-project.org/ and its documentatation section.
boxcox <- function(x,min,max,step) {
lambda <- seq(min,max,step) # you set lambda1
s <- length(lambda)
for (lambda in 1:s) # here you expect lambda is different from
# lambda1 and you make all computation with this new value of lambda
# you need to use also curly braces to include all rows between them
# into one cycle
n <- nrow(x)
if(lambda ==0) xL <- log(x) else xL <- ((x^lambda) - 1)/lambda
xLbar <- mean(xL)
t1 <- (-n/2)* log((1/n)*sum((xL - xLbar)^2))
t2 <- (lambda - 1)*sum(log(x))
l= t1 + t2
l
}
On 11 Oct 2006 at 0:28, Dale Steele wrote:
Date sent: Wed, 11 Oct 2006 00:28:21 -0400
From: Dale Steele <[EMAIL PROTECTED]>
To: [email protected]
Subject: [R] for loop not working in function
> I'm trying to write a small function (below) to compute Box & Cox
> transformations of x for arbitrary values of lambda. I'd like to
> specify a range of values for lamba (min,max,step) and am having
> trouble getting the for loop to work. Suggestions?
>
> Any pointers to resources for learning to write functions in R for
> neophyte programmers? Thanks. --Dale
>
>
> boxcox <- function(x,min,max,step) {
> lambda <- seq(min,max,step)
> s <- length(lambda)
> for (lambda in 1:s)
> n <- nrow(x)
> if(lambda ==0) xL <- log(x) else
> xL <- ((x^lambda) - 1)/lambda
> xLbar <- mean(xL)
> t1 <- (-n/2)* log((1/n)*sum((xL - xLbar)^2))
> t2 <- (lambda - 1)*sum(log(x))
> l= t1 + t2
> l
> }
>
> ______________________________________________
> [email protected] mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html and provide commented,
> minimal, self-contained, reproducible code.
Petr Pikal
[EMAIL PROTECTED]
______________________________________________
[email protected] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
