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

Posted by Ewan McDonnell
Ewan McDonnell
1,646 Points

I keep getting an message saying "make sure you declare the coordinates array". I've declared it using var coordinates.

I've tried a number of variants. This is my latest attempt at this exercise, to create a two-dimensional array:

var array1 = []; var array2 = [];

var coordinates = array1.concat(array2);

script.js 
var array1 = [];
var array2 = [];

var coordinates = array1.concat(array2);
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Objects</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

1 Answer

Steven Parker
Steven Parker
229,732 Points
Steven Parker
Steven Parker
229,732 Points

I'm not sure what task you are on, but here's what you should create for each of them:

  • for task 1, "coordinates" should be an empty array
  • for task 2, coordinates" should have another arrays inside it — and the inner one should have 2 items
  • for task 3, coordinates" should have  4  other arrays in it — and each of those should have 2 items

Also, I don't think the challenge is expecting any other variables to be created. Try full fulling the requirements of each step by using array literal(s) in the assignment.