Tan
Calculates the tangent of an angle that is entered in radians.
A number; the tangent of an angle.
Tan(number)
|
Parameter |
Description |
|---|---|
| number |
Angle, in radians, for which to calculate the tangent. |
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.
<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 = "">
<input type = "RESET"
</form>