Position of return in a function in R

Question

I would like to understand the position of "return" in the function which I created to calculate the mean of smartphone prices.

Here are all the prices in my dataset "smartphones"

smartphones$Price
[1] 4688 5088 5588 6388 4398 5998 7498 3298 2898 4498 2598 5998 3998 5498 2998 
4298 5598 2698 4998 3598

Here is the function that I've created:

mean.kevin <- function(dataVector)
{
   total = 0;
   n = length(dataVector);
   for (v in dataVector)
 {
   total = total + v

  } 
     return (total/n)
   }

mean.kevin(smartphones$Price)

By placing the return outside of the "for" loop will return the correct answer as shown below:

> mean.kevin(smartphones$Price)
[1] 4631

However, if I placed the return inside the "for" loop as such:

mean.kevin <- function(dataVector)
{
  total = 0;
  n = length(dataVector);
  for (v in dataVector)
 {
  total = total + v
  return (total/n)
  } 

 }

mean.kevin(smartphones$Price)

When I execute the code, the wrong answer will be given:

> mean.kevin(smartphones$Price)
[1] 234.4

I do not understand the difference between putting the return inside or outside the for loop in Rstudio. Thank you.

Answer 1

Inside you break the for loop and go out of the iteration at the first loop.

Here an example:

#Breaking the forloop function
f1<-function() {

   for (i in 1:20)
   {
     return(i)
   }

 }

#Right use of return function
 f2<-function() {   
   for (i in 1:20)
   {
   }
   return(i)
 }

f1()
[1] 1
f2()
[1] 20