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JavaScript JavaScript Basics (Retired) Creating Reusable Code with Functions Random Number Challenge, Part II Solution

Posted by delaney
delaney
7,743 Points

Uncaught ReferenceError: isNAN is not defined

//What am I doing wrong? //Here's my code

function getRandomNumber( lower, upper ) { if ( isNAN(lower) || isNaN(upper) ) { throw new Error('Both arguments must be numbers'); } return Math.floor(Math.random() * (upper - lower + 1)) + lower;

}

console.log( getRandomNumber( 'nine', 24 ) );

3 Answers

David Gardner
David Gardner
10,143 Points
David Gardner
David Gardner
10,143 Points

If you look closely at the error message it is saying "isNAN" does not exist as a function.This is due to a slight typo cause by capitalizing the 'A', you're second "isNaN()" is correct because the 'a' is lowercase, just change that and you are good to go!

function getRandomNumber( lower, upper ) { 
  if ( isNaN(lower) || isNaN(upper) ) { 
    throw new Error('Both arguments must be numbers'); 
  } 
  return Math.floor(Math.random() * (upper - lower + 1)) + lower;
}
Gabbie Metheny
Gabbie Metheny
33,778 Points

Thank you, David! Same problem here, I thought I was going crazy...

delaney
delaney
7,743 Points
delaney
delaney
7,743 Points

Not sure how i missed that! Thanks so much!

Monty King
Monty King
2,712 Points
Monty King
Monty King
2,712 Points

Thank you so much. Not sure how I did it too...