[R] strange error message

[Michael Rennie]

Hi, there

I have a loop that is producing data, but is also generating an error message 
that I can't understand.

Here's the loop and the error message:

> bio<-matrix(NA, ncol=9, nrow=366)
> W<-NULL
> M<- length(Day) #number of days iterated
> 
> for (i in 1:M)
+ {
+ 
+ 
+ if (Day[i]==1) W[i] <- Wo else W[i] <- (W[i-1]+(Gr[i]/Ef))
+ 
+ 
+ C<- p*CA*(W^CB)*(((comp[,3])^Xc)*(exp(Xc*(1-(comp[,3])))))*Pc
+ 
+ ASMR<- ACT*RA*(W^RB)*(((comp[,4])^Xa)*(exp(Xa*(1-(comp[,4])))))
+ 
+ SMR<- (ASMR/ACT)
+ 
+ A<- (ASMR-SMR)
+ 
+ F<- (FA*((comp[,2])^FB)*(exp(FG*p))*C)
+ 
+ U<- (UA*((comp[,2])^UB)*(exp(UG*p))*(C-F))
+ 
+ SDA<- (S*(C-F))
+ 
+ Gr<- (C-(ASMR+F+U+SDA))
+ 
+ bio<- cbind(W, C, ASMR, SMR, A, F, U, SDA, Gr)
+ 
+ }
There were 50 or more warnings (use warnings() to see the first 50)
> 
> warnings
function (...) 
{
    if (!(n <- length(last.warning))) 
        return()
    names <- names(last.warning)
    cat("Warning message", if (n > 1) 
        "s", ":\n", sep = "")
    for (i in 1:n) {
        out <- if (n == 1) 
            names[i]
        else paste(i, ": ", names[i], sep = "")
        if (length(last.warning[[i]])) {
            temp <- deparse(last.warning[[i]])
            out <- paste(out, "in:", temp[1], if (length(temp) > 
                1) 
                " ...")
        }
        cat(out, ..., fill = TRUE)
    }
}
> 
> dimnames (bio) <-list(NULL, c
("W", "C", "ASMR", "SMR", "A", "F", "U", "SDA", "Gr"))
> 
> 
> bio
               W        C     ASMR       SMR         A        F         U
  [1,]  9.200000 233.6647 107.5640  64.50050  43.06345 31.93755 15.840142


Also, does anyone know why I might be getting differences in the same 
calculation between R and Excel?  Is there any way to keep R from rounding your 
numbers, or to specify the # of decimal places you want for an element? 


-- 
Michael Rennie
M.Sc. Candidate
University of Toronto at Mississauga
3359 Mississauga Rd. N.
Mississauga ON  L5L 1C6
Ph: 905-828-5452  Fax: 905-828-3792