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JavaScript JavaScript Functions Arrow Functions Testing for Number Arguments

Yoan Halevy
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Yoan Halevy
Full Stack JavaScript Techdegree Student 2,964 Points
Posted by Yoan Halevy
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Yoan Halevy
Full Stack JavaScript Techdegree Student 2,964 Points

The code I have gives me back a value of "undefined". Can someone tell me why? 

const randomNumber = (lower, upper) => {
  Math.floor(Math.random() * (upper - lower + 1)) + lower;
  if (isNaN(lower) || isNaN(upper)) {
    throw Error ("You must select only numbers");
  }
}

// Call the function and pass it different values

console.log(randomNumber(1,5));
console.log(`${randomNumber(5,100)} is a random number between 5 and 100`);
console.log(randomNumber("six",987324));

1 Answer

Joseph Yhu
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Joseph Yhu
PHP Development Techdegree Graduate 48,637 Points

You have to return the random number, like this:

const randomNumber = (lower, upper) => {
  if (isNaN(lower) || isNaN(upper)) {
    throw Error ("You must select only numbers");
  }
  return Math.floor(Math.random() * (upper - lower + 1)) + lower;
}