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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Create a Two Dimensional Array

J P
J P
1,620 Points
Posted by J P
J P
1,620 Points

Hi, I'm having trouble with 2-dimensional arrays. I get a There was an error with your code: TypeError: 'undefined''.

Hope you can help!

script.js 
var coordinates = [ [1, 2] [0, 1] [1, 2] [0, 1] ];
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Objects</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

3 Answers

Paras Bokhari
Paras Bokhari
11,522 Points
Paras Bokhari
Paras Bokhari
11,522 Points

Hi Joseph,

You must add commas in order to separate each item within an array. That's why it's very common to enter each item in a two-dimensional array on a separate line.

const coordinates = [ 
    [1, 2],
    [0, 1],
    [1, 2],
    [0, 1] 
];

console.log(coordinates) // logs the array.

Please note: the last item within an array will not have an ending comma.

Hope this helps.

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,972 Points
KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,972 Points

Your arrays should be separated by commas

J P
J P
1,620 Points
J P
J P
1,620 Points

Thanks so much!