Javascript Math - atan Method

Description:

This method returns the arctangent in radians of a number. The atan method returns a numeric value between -pi/2 and pi/2 radians.

Syntax:

Math.atan( x ) ;

Here is the detail of parameters:

x : A number.

Return Value:

Returns the arctangent in radians of a number.

Example:

<html>
<head>
<title>JavaScript Math atan() Method</title>
</head>
<body>
<script type="text/javascript">

var value = Math.atan(-1);
document.write("First Test Value : " + value ); 
  
var value = Math.atan(.5);
document.write("<br />Second Test Value : " + value ); 

var value = Math.atan(30);
document.write("<br />Third Test Value : " + value ); 

var value = Math.atan("string");
document.write("<br />Fourth Test Value : " + value ); 
</script>
</body>
</html>

This will produce following result:

First Test Value : -0.7853981633974483
Second Test Value : 0.4636476090008061
Third Test Value : 1.5374753309166493
Fourth Test Value : NaN

To understand it in better way you can Try it yourself.