[R] Sequences

[David Winsemius]

Think about what i-1 would be the first time though the loop. R  
doesn't like 0 as an index. You are going to need to decide what you  
consider to the the "previous value" for the first element in your  
vector.

If you want cumulative sums, then look at the function cumsum
?cumsum


On Apr 7, 2009, at 8:13 AM, Melissa2k9 wrote:

>
> Hi,
>
> I am trying to make a sequence and am  using a for loop for this. I  
> want to
> start off with an initial value ie S[0]=0 then use the loop to  
> create other
> values. This is what I have so far but I just keep getting error  
> messages.
>
> #To calculate the culmulative sums:
>
> s<-rep(0,207)                                #as this is the length  
> of the
> vector I know I will have
> s<-as.vector(s)
> s[0]<-0
> for (i in 1:length(lambs))                    # where lambs is a  
> vector of
> length 207 consisting of temperature
>                                                                     
> values
>
>
> {
> 	s[i]<-s[i-1]-mean(lambs)
> }
>
> I continually get the error message:
>
> Error in s[i] <- s[i - 1] - mean(lambs) : replacement has length zero
>
>
> When I merely use s[i]<-i-mean(lambs) it works so there is obviously
> something wrong with the s[i-1] but i cant see what. All I want is  
> for each
> S[i] to be the previous value for S - the mean!
> -- 
> View this message in context: http://www.nabble.com/Sequences-tp22927714p22927714.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> R-help at r-project.org 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.

David Winsemius, MD
Heritage Laboratories
West Hartford, CT