First of all, I am initializing an empty vector and I want to populate it whenever I call the function. I want the element added to be added to the empty vector and so on but, when I call the function nothing happens so I not sure what I am doing wrong. Any help is appreciated.
empty_vec<-c()
func<-function(num){
for (numbers in num) {
i<-sqrt(numbers)
empty_vec<- c(empty_vec,i)
}
}
func(4) # When calling the func,4 isn't getting added to the empty_vec.
You should initialize empty_vec within func and return it (so you should put empty_vec at the bottom as well), e.g.,
func <- function(num) {
empty_vec <- c()
for (numbers in num) {
i <- sqrt(numbers)
empty_vec <- c(empty_vec, i)
}
empty_vec
}
such that
> func(c(4, 5, 6, 7))
[1] 2.000000 2.236068 2.449490 2.645751
Since what you are doing is to calculate sqrt, you can do it just via
> sqrt(c(4,5,6,7))
[1] 2.000000 2.236068 2.449490 2.645751
empty_vec is unnecessary for many easily-defined operations, even if it's not a built-in function. For example, func <- function(num) log(num) * sqrt(num) + 10 (or whatever other arbitrary operations you like) can simply take a vector as input: func(c(4, 6, 9)).
<-will not overwrite the value of theempty_vecoutside offunc, it will make a "copy" of the data within the function that masks it, and when the function exits, that updated copy will cease to exist. (2) There are functions for doing that (see<<-andassign), but they should not be used regularly, and suggest a poor design. I discourage them.