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

Bryan Smith
Bryan Smith
2,864 Points
Posted by Bryan Smith
Bryan Smith
2,864 Points

isNaN error

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

console.log( getRandomNumber( 9, 24 ) );
console.log( getRandomNumber( 1, 100 ) );
console.log( getRandomNumber( 200, 'five hundred' ) );
console.log( getRandomNumber( 1000, 20000 ) );
console.log( getRandomNumber( 50, 100 ) );

the above code is what i entered.

I am getting this error message: Uncaught ReferenceError: isNan is not defined

2 Answers

Erik McClintock
Erik McClintock
45,783 Points
Erik McClintock
Erik McClintock
45,783 Points

Bryan,

At a glance, it looks to me like this may be just a simple capitalization error. The error is telling you that you have tried using something that has not been previously defined; in this case, that something is 'isNan', and that is correct: 'isNan' has not been defined anywhere. You want to use 'isNaN', with the last 'n' capitalized. Try correcting that and see what you get.

Erik

Bryan Smith
Bryan Smith
2,864 Points
Bryan Smith
Bryan Smith
2,864 Points

omg thanks! haha. I was only looking at the first isNaN which was correct. debugging JavaScript can probably drive one crazy! looking for an extra space here, a mis-capitalized letter there.

Thanks!

Erik McClintock
Erik McClintock
45,783 Points
Erik McClintock
Erik McClintock
45,783 Points

Oh, totally. Debugging ANY language can be a nightmare, due to how specific and exact we must be with our syntax everywhere. Once you've got something running that is hundreds or thousands of lines of code, it can absolutely be one of the worst things on the planet haha. Just always make sure to constantly save versions of your code and try to run/compile/refresh/whathaveyou to test every little change to every little thing (like, EVERY LITTLE CHANGE) as you're going along, and it will help to isolate the potential error zones in your code throughout production.

Happy coding!

Erik