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

Posted by Aldo Martinez
Aldo Martinez
3,883 Points

My console.log return an undefined object and I don't get why.

Hi all,

I'am having some trouble with consoling the items of an array.

I loop through the array using a for loop and console log each item, however a undefined obj is returned as well and I don't get why.

here is my code: 

let temperatures = [100,90,99,80,70,65,30,10];

for(let i = 0; i < temperatures.length -1; i++){
  let variab = temperatures[i];
  console.log(variab);
  }

Thank you!

script.js 
var temperatures = [100,90,99,80,70,65,30,10];


for(let i = 0; i < temperatures.length -1; i++){
  let var = temperatures[i];
  console.log(var);
  }
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

1 Answer

Unsubscribed User
.a{fill-rule:evenodd;}techdegree
Unsubscribed User
Front End Web Development Techdegree Student 33,900 Points

Hi Aldo,

in the for loop parameters: Delete the "-1". Otherwise you don't loop til the last item. Because you start the loop with zero and with "i < temperatures.length" you already are fine.

Then in code block you do not need to define a variable.

Just console.log directly what you put in the variable. :)

Try out, it should work. If not let me know.

Happy coding, Nils

Aldo Martinez
Aldo Martinez
3,883 Points

for(let i = 0; i < temperatures.length; i++){ console.log(temperatures[i]); }

worked out, thanks.

I used the var to get rid of the "undefined", but didn't help since console.log is a function.

Unsubscribed User
.a{fill-rule:evenodd;}techdegree
Unsubscribed User
Front End Web Development Techdegree Student 33,900 Points

Great... Happy, I could help. :)