Sinc function

<%
    ' Copyright (c) 2008, reusablecode.blogspot.com; some rights reserved.
    '
    ' This work is licensed under the Creative Commons Attribution License. To view
    ' a copy of this license, visit http://creativecommons.org/licenses/by/3.0/ or
    ' send a letter to Creative Commons, 559 Nathan Abbott Way, Stanford, California
    ' 94305, USA.
 
    Const M_PI = 3.14159265358979323846
 
    ' Unnormalized sinc function.
    function sinc(x)
        sinc = sin(x) / x
    end function
 
    ' Normalized sinc function.
    ' REQUIRES: constant M_PI
    function nsinc(x)
        sinc = sin(M_PI * x) / (M_PI * x)
    end function
%>