如何在 R 中允许用户在最小-最大范围内输入？

Question

Good afternoon.

My question is very simple.

I'm wanting to retrieve some n user inputs ( a vector of length n ). Only values between 0 and 1 are accepted.

I know how to retrieve values with scan function but i don't know how to force users to enter only values in [min-max] interval.

Thank you for help !

Code:

x <- scan(,n=3)

Answer 1

One way can be using a while loop :

stayInLoop <- TRUE
N<-3 # number of elements in vector

while(stayInLoop){
  print("Please insert x") 
  x <- scan(,n=N) #readLines(,n=N)

 if (any(x<0) | any(x>1)) {
    print("Re-enter the values, as valid values can be between 0 and 1") 
    x <- scan(,n=N)
  }

  stayInLoop<-any(x<0) & any(x>1)

}

[1] "Please insert x"
1: 1
2: 2
3: 3
Read 3 items
[1] "Re-enter the values, as valid values can be between 0 and 1"
1: 0.2
2: 0.2
3: 0.4
Read 3 items

> x
[1] 0.2 0.2 0.4