User Guide
276 CFML Language Reference
ASin
Returns the arcsine of a number in radians. The arcsine is the angle whose sine is
number.
See also Sin, Cos, Pi, and Tan.
Syntax ASin(
number
)
number
Sine of the angle that is to be calculated. This value must be between 1 and -1.
Usage The range of the result is -π/2 to π/2 radians. To convert degrees to radians, multiply
degrees by π/180. To convert radians to degrees, multiply radians by 180/π.
Examples <!--- This example shows how to use ASin --->
<HTML>
<HEAD>
<TITLE>ASin Example</TITLE>
</HEAD>
<BODY BGCOLOR=silver>
<H3>ASin Example</H3>
<!--- output its arcsine value --->
<CFIF IsDefined("FORM.SinNum")>
<CFIF IsNumeric(FORM.SinNum)>
<CFIF FORM.SinNum LESS THAN OR EQUAL TO 1>
<CFIF FORM.SinNum GREATER THAN OR EQUAL TO -1>
ASin(<CFOUTPUT>#FORM.SinNum#</CFOUTPUT>) =
<CFOUTPUT>#Evaluate(ASin(FORM.sinNum))# Radians</
CFOUTPUT>
<BR>
or
<BR>ASin(<CFOUTPUT>#FORM.SinNum#</CFOUTPUT>) =
<CFOUTPUT>#Evaluate(ASin(FORM.sinNum) * 180/Pi())#
Degrees</CFOUTPUT>
<CFELSE>
<!--- if it is less than negative one, output an error message --->
<H4>Please enter the sine of the angle that is to be
calculated in degrees and radians. This value must be between 1 and -1,
inclusive.</H4>
</CFIF>
<CFELSE>
<!--- if it is greater than one, output an error message --->
<H4>Please enter the sine of the angle that is to be calculated in
degrees and radians. This value must be between 1 and -1, inclusive.</H4>
</CFIF>
<CFELSE>
<!--- if it is empty, output an error message --->