# fiBonacci.R # playing with recursion coz bored # Stephen Pratt 25/08/2009 4:19:50 PM ####################################################################### # Recursive version of Fibonacci series (very inefficient) fiBonacci <- function(n, count = T, first = T){ if(first) i <<- 0 if(count) i <<- i + 1 if(as.integer(n) %in% 0:1) return(n) fib <- fiBonacci(n = n-1, co=count, f=F) + fiBonacci(n = n-2, co=count, f=F) ifelse(first, return(list(fib = fib, i = i)), fib) } ####################################################################### # dreaded for-loop version of Fibonacci series fiB <- function(n){ fib <- NULL fib[1] <- 0 # indexes offset by 1 because R can't handle x[0] fib[2] <- 1 for(i in 3:(n+1)) fib[i] <- fib[i-1] + fib[i-2] return(fib) }