<!--Last Updated: $Revision: 1.4 $ on $Date: 2001/02/05 18:15:00 $ -->
<!-- Javascript file, containing functions used by calculations -->   
var range="";
var styleObj="";
var isNav4=false,isNav5=false, isIE4=false;
	
   if(navigator.appName=="Netscape")
	{
      if (navigator.appVersion < "5")
      {
         isNav4 = true;
      }  
		if (navigator.appVersion > "4")
      {
         isNav5 = true;
      }  
	}
   else
	{
		isIE4=true;
		range="all.";
		styleObj=".style";
	}
   
   function dollarToNumb(str)
   {
      var id;
      str+="";
      if(str.length==0) return 0;
         while((str.substring(0,1) < "1" || str.substring(0,1) > "9")&&str.substring(0,1) != "-")
         {
            str=str.substring(1);
            if(str.length==0)
                return 0
         }
         id=0;
         while(1)
         {
            id=str.indexOf(",")
            if(id == -1) return parseFloat(str);
               str=str.substring(0,id)+str.substring(id+1);
         }
         return 0;
   }

   function numbToDollar(numb)
   {
      var dif,id,str="",lefts="",rights="00",i;
      str=numb+"0";
      while((str.substring(0,1) < "1" || str.substring(0,1) > "9")&&str.substring(0,1) != "-")
        {
        if(str.substring(0,1)==".")
                break;
        str=str.substring(1);
        if(str.length==0)
            return "0"
        }
      while(1)
         {   
         id=str.indexOf(",");
         if(id > -1)
         {
            lefts=str.substring(0,id);
            rights=str.substring(id+1,str.length);
            str=lefts+rights;
         }
         else
            break;
         }
         id=str.indexOf(".");
         if(id > -1)
         {
            lefts=str.substring(0,id);
            rights=str.substring(id+1,str.length-1);
         }
         else
         {
            lefts=str.substring(0,str.length-1);
         }
         dif=document.places - rights.length;
         if(dif > 0)
            for(i=0;i<dif;i++)
                rights+="0";
         if(dif < 0)
            rights=rights.substring(0,document.places);
         if(lefts.length==0)lefts="0";
            if(lefts.length > 6 && lefts.substring(0,1) != "-")
               lefts=lefts.substring(0,lefts.length-6)+","+lefts.substring(lefts.length-6);
            if(lefts.length > 3 && lefts.substring(0,1) != "-")
               lefts=lefts.substring(0,lefts.length-3)+","+lefts.substring(lefts.length-3);
               lefts=""+lefts;
            if(document.places==0)
               return lefts;
            else
            {
               return lefts+"."+rights;
            }
   }

   function getMonthlyPayment(p,i,n)
   {
      var principal=dollarToNumb(p);
      var interest=i/100;
      interest/=12;
      var periods=n;
      var p1=Math.pow(1+interest,periods);
      var payment=interest/(1-(1/p1))*principal;
      return payment;
   }

   function getNumbPayments(newBal,newInterest,newPayment)
   {
      if(newPayment/(newPayment-newInterest/12/100*newBal) <= 0 )
      return 1000000;//can't take log
      var num=Math.log(newPayment/(newPayment-newInterest/12/100*newBal));
      var den=Math.log(1+newInterest/12/100);
      return num/den;//new number of payments
   }

   function getInterest(principal,rate,months,payAmount,NumPayments)
   {
      var princ=principal;
      rate=rate/1200;
      for(var x=0;x<months;x++)
      {
          princ+=princ*rate;
          if(x<NumPayments)
              princ-=payAmount;
      }
      princ=Math.round(princ*100)/100;
      princ-=principal;
      return princ;
   }