Tan |
Description
Calculates the tangent of an angle that is entered in radians.
Returns
A number; the tangent of an angle.
Category
Mathematical functions
Function syntax
    Tan(number)
See also
Atn, Cos, ACos, Sin, ASin, Pi
Parameters
Parameter | Description
number | Angle, in radians, for which to calculate the tangent.
Usage
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 can return a very small number (such as 6.12323399574E-017) for angles that should produce 0 and can return a very large number (such as 1.63312393532E+016) for infinity or not a number. To test for a 0 value, check whether the value is less than 0.0000000000001. To test for an infinite value, check whether the value is more than 1E15.
Example
    <h3>Tan Example</h3>
    <!--- Calculate tangent if form has been submitted --->
    <cfif IsDefined("FORM.tanNum")>
    <!--- Make sure input is a number --->
       <cfif IsNumeric(#FORM.tanNum#)>
    <!--- Convert degrees to radians, call the Tan function. --->
            <cfset tanValue=#Tan((Form.tanNum * PI()) / 180)#>
    <!--- 0.0000000000001 is the function's precision limit.
         If absolute value of returned value is
         less, set result to 0 --->
            <cfif Abs(tanValue) LT 0.0000000000001>
               <cfset tanValue=0>
            </cfif>
            <cfoutput>
              Tan(#FORM.tanNum#) = #tanValue#<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 tangent:
        <br><input type = "Text" name = "tanNum" size = "15">
        <br><br>
        <input type = "Submit" name = "">&nbsp;&nbsp;
        <input type = "RESET"
    </form>

number |
Angle, in radians, for which to calculate the tangent.