ICS3U1 Unit 2 Activity 4: Question 4

// Date: July 21, 2017
// Purpose: To reduce a given fraction by finding the greatest common denominator (GCD or GCF)

// This line makes the button, btnCalculate wait for a mouse click
// When the button is clicked, the calculateReduced function is called
btnCalculate.addEventListener(MouseEvent.CLICK, calculateReduced);

// These lines make the TextInput wait for a mouse click
// When any of these components are clicked, the clearLabels function is called
txtinNumerator.addEventListener(MouseEvent.CLICK, clearLabels);
txtinDenominator.addEventListener(MouseEvent.CLICK, clearLabels);

// Declare Global Variables
var Numerator:Number;     // The numerator of the fraction
var Denominator:Number;  // The denominator of the fraction
var Factor:Number; // The greatest common denominator of the numerator and the denominator

// This is the reduce function
// e:MouseEvent is the click event experienced by the button
// void indicates that the function does not return a value
function calculateReduced(e:MouseEvent):void
{
    getData();
    lblResult.text = Numerator + "/" + Denominator + " can be reduced to " + (Numerator / gcd(Numerator,Denominator)) + "/" + (Denominator / gcd(Numerator,Denominator))
}

// This is function gcd
// It uses the Eculidian Algorithm for calculating the GCD of two numbers
function gcd(a:Number,b:Number):Number
{
    var tmp:Number;
    //Swap the numbers so a >= b
    if(a < b)
    {
        tmp = a;
        a = b;
        b = tmp;
    }
    //Find the gcd
    while(b != 0)
    {
        tmp = a % b;
        a = b;
        b = tmp;
    }
    return a;
}

// This is the getData function
// It retrieves the numerator and the denominator from their respective TextInput boxes
function getData()
{
    Numerator = Number(txtinNumerator.text);
    Denominator = Number(txtinDenominator.text);
}

// This is the clearLabels function
// e:MouseEvent is the click event experienced by the textInput
// void indicates that the function does not return a value
function clearLabels(e:MouseEvent):void
{
     lblResult.text = "";
}