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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Iterating through an Array

Posted by Aaron Hasbrouck
Aaron Hasbrouck
1,295 Points

I don't understand what I'm doing wrong

Hi, I'm really not understanding why I'm getting an error for my array being listed out of order.

script.js 
var temperatures = [100,90,99,80,70,65,30,10];
var i
function printList( list ){
  var listHTML = '<ol>';
for ( i = 0; i < temperatures.length; i += 1){
  listHTML += '<li>' + list[i] + '</li>';
  }
  listHTML += '</ol>';

}
console.log(i);
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>
Andrew Elliott
Andrew Elliott
3,306 Points

Your problem is that you are doing your loop in an improper way. Here's what it should look like this:

script.js 
var temperatures = [100,90,99,80,70,65,30,10];
var i
function printList( list ){
  var listHTML = '<ol>';
  for (temp in temperatures){
    listHTML += '<li>' + temp + '</li>';
  }
  listHTML += '</ol>';
}
console.log(i);
// ^^ I think that should be right. Correct me if i'm wrong. I am unable to test it.

1 Answer

Benjamin Larson
Benjamin Larson
34,055 Points
Benjamin Larson
Benjamin Larson
34,055 Points

You have a lot more going on in your code than the challenge is really looking for in terms of the printList function and printing HTML list items. These should be removed otherwise the challenge will fail.

The for loop declaration is good, although you could condense things by declaring the i variable inside of it. You'll need to move your console.log function inside the for loop in order for it to traverse each of the values in the array. Finally, console.log(i) will only log the index. You need to log the value of the temperature array at that index, so give that a shot.

for (var i = 0; i < temperatures.length; i += 1) {
  // add console.log() here
}