CFLib.org – Common Function Library Project

Description:
Returns the inverse hyperbolic cotangent of a value. All angles are expressed in radians.

Return Values:
Returns a numeric value or string.

Example:

<CFSET x=1.5>
<CFSET y=0>
<CFSET z=-1.5>
<CFOUTPUT>
Given x=#x#<BR>
Given y=#y#<BR>
Given z=#z#<BR>
The Acoth of #x# is: #Acoth(x)# radians<BR>
The Acoth of #y# is: #Acoth(y)# radians<BR>
The Acoth of #z# is: #Acoth(z)# radians<BR>
</CFOUTPUT>

Parameters:

Full UDF Source:

/**
 * Returns the inverse hyperbolic cotangent of a value.
 * 
 * @param x      x>1, x<-1 
 * @return Returns a numeric value or string. 
 * @author Rob Brooks-Bilson (rbils@amkor.com) 
 * @version 1, November 29, 2001 
 */
function Acoth(x){
  if (x lt -1)
    return Log((x+1)/(x-1))/2;
  else
    if (x gt 1)
      return Log((x+1)/(x-1))/2;
  else
    return "undefined";
}