R：使用 for 循环创建 1/n 权重的向量

Question

For the sake of making this general enough to be useful for others, I have six friends:

friends <- c("luke", "leia", "han", "chewy", "lando", "obi")

That I am trying to give them each a portion of cake using a for loop

portions <- for (portion in length(friends)){
                 portion = 1/portion
}

My code returns the correct portion size (~16%), but does not populate my portions vector with what I was hoping for: (0.16,0.16,0.16,0.16,0.16,0.16)

Cutsie examples aside, I am looking to for a solution which can be applied to creating weights for several hundred variables.

Any help would be greatly appreciated!

Answer 1

You could use

prop.table(table(friends))

#friends
#chewy   han lando  leia  luke   obi 
#0.167 0.167 0.167 0.167 0.167 0.167 

Or

table(friends)/length(friends)

Answer 2

We can just do rep on the 1/length(friends) and it would give the expected output without any other calculations

rep(1/length(friends), length(friends))
#[1] 0.1666667 0.1666667 0.1666667 0.1666667 0.1666667 0.1666667

---

In the for loop, we are only assigning to portion each time and it gets updated. Instead, an optioin is to pre-assign a vector and assign it to it

portion <- numeric(length(friends))
for(i in seq_along(friends)) portion[i] <- 1/length(friends)
portion
#[1] 0.1666667 0.1666667 0.1666667 0.1666667 0.1666667 0.1666667