How to calculate distance between two places using respective latitude and longitude values?

Question

I know this is a repetitive question but I have to ask because my code is not working. I have no clue why not.

My code:

<!DOCTYPE html>
<html>
<head>
<script>
function displayDistance()
{

var R = 6371; // km
var dLat = (23.87284-23.76119).toRad();
var dLon = (90.39603-90.43491).toRad(); 
var a = Math.sin(dLat/2) * Math.sin(dLat/2) + 
        Math.cos(23.76119.toRad()) * Math.cos(23.87284.toRad()) *
        Math.sin(dLon/2) * Math.sin(dLon/2); 
var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a)); 
var d = R * c;
document.getElementById("demo").innerHTML=d;
}
</script>
</head>
<body>
<div id="demo"></div>
<button type="button" onclick="displayDistance()">Display Distance</button>

</body>
</html>

But just nothing happens. Thanks

score 2 · Accepted Answer · edited May 23 '17 at 11:56

toRad is not a native javascript function. You must declare it before using it.

/** Converts numeric degrees to radians */
if (typeof(Number.prototype.toRad) === "undefined") {
  Number.prototype.toRad = function() {
    return this * Math.PI / 180;
  }
}

Code from here : toRad() Javascript function throwing error

You can check this jsfiddle : http://jsfiddle.net/ySsQ3/

By the way, you really should put your javascript code at the end of the body (and not in the head)

How to calculate distance between two places using respective latitude and longitude values?

1 Answers1