CFLib.org – Common Function Library Project

Description:
Multiply two complex numbers, or a real and a complex number, or two real numbers and return the result stored as a structure.

Return Values:
Returns a structure.

Example:

<cfset a = ComplexNum(3,4)>
<cfset b = ComplexNum(1,-10)>
<cfset c = ComplexNumMultiply(a,b)>
<cfset d = ComplexNumMultiply(a,3)>
<cfoutput>
    (#ComplexNumToString(a)#) * (#ComplexNumToString(b)#) = #ComplexNumToString(c)#<br>
    (#ComplexNumToString(a)#) * 3 = (#ComplexNumToString(d)#)
</cfoutput>

Parameters:

Full UDF Source:

/**
 * Multiply two complex numbers.
 * Note that this function uses complex numbers stored as structures by the ComplexNum() UDF also available in this library.  The ComplexNum() function is also required for this UDF to function.
 * 
 * @param Multiplicand      Structure containing a complex number or a real number. 
 * @param Multiplier      Structure containing a complex number or a real number. 
 * @return Returns a structure. 
 * @author Matthew Walker (matthew@electricsheep.co.nz) 
 * @version 1, November 15, 2001 
 */
function ComplexNumMultiply(Multiplicand,Multiplier) {
    var ComplexProduct = StructNew();
    var ComplexMultiplicand = 0;
    var ComplexMultiplier = 0;
    var R = 0;
    var I = 0;
            
    if ( IsStruct(Multiplicand) )
        ComplexMultiplicand = Multiplicand;
    else    
        ComplexMultiplicand = ComplexNum(Multiplicand,0);    
    if ( IsStruct(Multiplier) )
        ComplexMultiplier = Multiplier;
    else    
        ComplexMultiplier = ComplexNum(Multiplier,0);
                
    R = ComplexMultiplicand.R * ComplexMultiplier.R - ComplexMultiplicand.I * ComplexMultiplier.I;
    I = ComplexMultiplicand.R * ComplexMultiplier.I + ComplexMultiplicand.I * ComplexMultiplier.R;
    StructInsert(ComplexProduct, "R", R);
    StructInsert(ComplexProduct, "I", I);
    return ComplexProduct;
}