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# 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.

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