ColdFusion 9.0 Resources

Atn

Description

Arctangent function. The arctangent is the angle whose tangent is number.

Returns

The arctangent, in radians, of a number.

Function syntax

Atn(number)

Parameters

Parameter	Description
`number`	Tangent of an angle

Usage

The range of the result is -p/2 to p/2 radians. To convert degrees to radians, multiply degrees by p/180. To convert radians to degrees, multiply radians by 180/p.

Example

<h3>Atn Example</h3> 
<!--- Output its Atn value. ---> 
<cfif IsDefined("FORM.AtnNum")> 
    <cfif IsNumeric(FORM.AtnNum)> 
        Atn(<cfoutput>#FORM.AtnNum#</cfoutput>) is 
    <cfoutput>#Atn(FORM.AtnNum)# radians is #Atn(FORM.AtnNum * 180/PI())# Degrees</cfoutput> 
    <cfelse> 
<!--- If it is empty, output an error message. ---> 
        <h4>Enter a number</h4> 
    </cfif> 
</cfif> 
<form action = "evaltest.cfm" method="post"> 
    <p>Enter a number to get its arctangent in Radians and Degrees 
    <br><input type = "Text" name = "atnNum" size = "25"></p> 
    <p><input type = "Submit" name = ""> <input type = "RESET"></p> 
</form>

Atn