ColdFusion 9.0 Resources

Sin

Description

Calculates the sine of an angle that is entered in radians.

Returns

A number; the sine of the angle.

Function syntax

Sin(number)

Parameters

Parameter	Description
`number`	Angle, in radians for which to calculate the sine.

Usage

The range of the result is -1 to 1.

To convert degrees to radians, multiply degrees by p/180. To convert radians to degrees, multiply radians by 180/p.

Note: Because the function uses floating point arithmetic, it returns a very small number (such as 6.12323399574E-017) for angles that should produce 0. To test for a 0 value, check whether the value is less than 0.0000000000001.

Example

<h3>Sin Example</h3> 
<!--- Calculate sine if form has been submitted ---> 
<cfif IsDefined("FORM.sinNum")> 
<!--- Make sure input is a number ---> 
    <cfif IsNumeric(#FORM.sinNum#)> 
<!--- Convert degrees to radians, call the Sin function. ---> 
<cfset sinValue=#Sin((Form.sinNum * PI()) / 180)#> 
<!--- 0.0000000000001 is the function's precision limit. 
    If absolute value of returned sine value is  
    less, set result to 0 ---> 
<cfif Abs(sinValue) LT 0.0000000000001> 
    <cfset sinValue=0> 
</cfif> 
<cfoutput> 
        Sin(#FORM.sinNum#) = #sinValue#<br><br> 
</cfoutput> 
    <cfelse> 
<!--- If input is not a number, show an error message ---> 
        <h4>You must enter a numeric angle in degrees.</h4> 
    </cfif> 
</cfif> 
<form action = "#CGI.script_name#" method="post"> 
Enter an angle in degrees to get its sine: 
<br><input type = "Text" name = "sinNum" size = "15"> 
<br><br> 
<input type = "Submit" name = "">&nbsp;&nbsp; 
<input type = "RESET" 
</form>

Sin