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JavaScript JavaScript Functions Arrow Functions Testing for Number Arguments

Posted by Alexis Scriven
Alexis Scriven
2,246 Points

I am getting an error that isNAN is not defined, but my code is the exact same as the video.

function getRandomNumber(lower, upper = 100) {
  if ( isNAN(lower) || isNAN(upper) ) {
    throw Error('Both arguments must be numbers.');
  }
  return Math.floor(Math.random() * (upper - lower + 1)) + 1;
}

console.log( getRandomNumber(1, 6));
console.log( getRandomNumber(10, 100));
console.log( getRandomNumber(200, 'three hundred'));

What is incorrect?

Mod edit: added markdown for code readability. Check out the "markdown cheatsheet" below the comment box for syntax examples.

2 Answers

Jennifer Nordell
seal-mask
STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi there, Alexis Scriven! It's very close to the video but not exactly like it :smiley: In two places you have typed: isNAN instead of isNaN. Note the lower case "a" instead of the uppercase "A" as you have it. This is all case-sensitive.

Hope this helps! :sparkles:

Alexis Scriven
Alexis Scriven
2,246 Points

Ah, I see it now. Thank you for your help, Jennifer!

wildgoosestudent
wildgoosestudent
11,274 Points
wildgoosestudent
wildgoosestudent
11,274 Points

I just had this issue too! Thanks for posting :)