[R] Can't get sample function from "An Introduction to R" to work

[Peter Dalgaard]

"Bret Collier" <bret at tamu.edu> writes:

> David,
> If below is exactly what you typed, check your code again, I think you
> are missing a '}' after the last 2 parentheses.

That's not supposed to cause a syntax error, just another '+'.
I can copy and paste the code as written and not get an error:

> twosam<-function(y1, y2) {
+ n1<-length(y1);n2 <-length(y2)
+ yb1<-mean(y1); yb2<-mean(y2)
+ s1<-var(y1);s2<-var(y2)
+ s<-((n1-1)*s1 + (n2-1)*s2)/(n1+n2-2)
+ tst<-(yb1-yb2)/sqrt(s*(1/n1+1/n2))
+ }
>

Perhaps this was the 1st time David got his typing right? The error is
of the sort you'd get if you had 

 s<-((n1-1)*s1 + (n2-1)*s2/(n1+n2-2)

or

 tst<-(yb1-yb2)/sqrt(s*1/n1+1/n2))

 
> HTH,
> Bret
> 
> >>> David Groos <david.groos at mpls.k12.mn.us> 7/15/2005 3:40:01 PM >>>
> I'm trying to figure out R, a piece at a time, hours at a time...  I 
> was trying to copy the sample function in, "An Introduction to R"  (for
> 
> version 2.1.0) by W. N. Venables, D. M. Smith, page 42.  Section 10.1 
> "Simple examples" provides a sample function which I tried to duplicate
> 
> (I'm using Mac OS X 10.3.9, and "R for Mac OS X Aqua GUI v1.11).  The 
> following is what I typed and the last line is R's response when I hit
> 
> the return key after the penultimate line.  I've re-checked and 
> re-typed the code many times to no avail.  I wasn't able to find this 
> issue using search options, either.  Any help is GREATLY appreciated!
> 
>  > twosam<-function(y1, y2) {
> + n1<-length(y1);n2 <-length(y2)
> + yb1<-mean(y1); yb2<-mean(y2)
> + s1<-var(y1);s2<-var(y2)
> + s<-((n1-1)*s1 + (n2-1)*s2)/(n1+n2-2)
> + tst<-(yb1-yb2)/sqrt(s*(1/n1+1/n2))
> Error: syntax error
> 


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   O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
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