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

Posted by amirbizimana
amirbizimana
9,639 Points

Help ! Au secours ! Tasukete !

I keep getting a syntax error, something seems to be wrong with my console or something else (for loop looks okay i think...)

script.js 
var temperatures = [100,90,99,80,70,65,30,10];
for ( i = 100; i < temperatures.length ; i -=1){
  console.log(temperature);
}
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

2 Answers

Eric Butler
Eric Butler
33,512 Points

Amir, You want to initialize your loop variable to the index of the first item in an array, not its value -- and an array index starts at 0. Also, you want to increment the variable up, not down, so that the loop increments forward through each item in the array. Finally, you need to add the index variable as the key when you are console-logging the value, so that only 1 specific value is logged out for each iteration of the loop, instead of the entire array over and over again. So it should be:

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

Does all that make sense? Hope this helps.

amirbizimana
amirbizimana
9,639 Points

oh that awesome it worked out and i understood what i was doing wrong. Thanks for that detailed explanation Eric !

Chris Jardine
Chris Jardine
13,299 Points
Chris Jardine
Chris Jardine
13,299 Points

Hi Amir I think you should have "var i = 100;"

for ( var i = 100; i < temperatures.length ; i -=1){
  console.log(temperature);
}