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ralgorithmradix

Algorithm that gives you any number n in base 10 in base 3

I need to write an algorithm that gives you any number n in base 3 in R. So far I wrote that :

vector <- c(10, 100, 1000, 10000)

ternary <- function(n) { while (n != 0) {

  {q<- n%/%3}

  {r <- n%%3}

  {return(r)}

  q<- n  } 

sapply(vector, ternary)}

I thought that by applying sapply( vector, ternary) it would give me all the r for any given n that I would put in ternary(n). My code still gives me the "last r" and I don't get why.

Solution

  • This is the straightforward implementation of what I have learned to do by hand in nth grade (don't remember exactly when).

    base3 <- function(x){
    y <- integer(0)
    while(x >= 3){
        r <- x %% 3
        x <- x %/% 3
        y <- c(r, y)
    }
    y <- c(x, y)
    y
}

base3(10)
#[1] 1 0 1

base3(5)
#[1] 1 2