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function formatNum(Vnum) {

   if(Vnum > 99000000) {
   alert("High value, not able to format");
   focus();
   } else {
   
   var V10million = parseInt(Vnum / 10000000);

   var V1million = (Vnum % 10000000)  / 1000000;
      if(V1million / 1000000 == 1) {
      V1million = 1;
      } else
      if(V1million < 1) {
      V1million = "0";
     } else {
      V1million = parseInt(V1million,10);
     }

    var V100thousand = (Vnum % 1000000)  / 100000;
      if(V100thousand / 100000 == 1) {
      V100thousand = 1;
      } else
      if(V100thousand < 1) {
      V100thousand = "0";
     } else {
      V100thousand = parseInt(V100thousand,10);
     }

   var V10thousand = (Vnum % 100000)  / 10000;
      if(V10thousand / 10000 == 1) {
      V10thousand = 1;
      } else
      if(V10thousand < 1) {
      V10thousand = "0";
      } else {
      V10thousand = parseInt(V10thousand,10);
      }

   var V1thousand = (Vnum % 10000)  / 1000;
      if(V1thousand / 1000 == 1) {
      V1thousand = 1;
      } else
      if(V1thousand < 1) {
      V1thousand = "0";
     } else {
      V1thousand = parseInt(V1thousand,10);
     }

   var Vhundreds = (Vnum % 1000)  / 100;
      if(Vhundreds / 100 == 1) {
      Vhundreds = 1;
      } else
      if(Vhundreds < 1) {
      Vhundreds = "0";
     } else {
      Vhundreds = parseInt(Vhundreds,10);
     }

   var Vtens = (Vnum % 100)  / 10;
      if(Vtens / 10 == 1) {
      Vtens = 1;
      } else
      if(Vtens < 1) {
      Vtens = "0";
     } else {
      Vtens = parseInt(Vtens,10);
     }

   var Vones = (Vnum % 10)  / 1;
      if(Vones / 1 == 1) {
      Vones = 1;
      } else
      if(Vones < 1) {
      Vones = "0";
     } else {
      Vones = parseInt(Vones,10);
     }

  //START UPGRADE
var Vcents = 0;

if(Vnum % 1 * 100 < 1) {
   Vcents = 0;
   } else {
   Vcents = parseInt(((eval(Vnum % 1) * 100)),10);
   }
//END UPGRADE

 if(Vcents < 1) {
  Vcents = "00";
  }
  else
  if(Vcents % 10 == 0) {
  Vcents = Vcents + "0";
  }
  else
  if(Vcents % 10 == Vcents) {
  Vcents = "0" + Vcents;
  } else {
  Vcents = Vcents;
  }

  if(Vcents == "900") {
  Vcents = "90";
  } else
  if(Vcents == "800") {
  Vcents = "80";
  } else 
  if(Vcents == "700") {
  Vcents = "70";
  } else 
  if(Vcents == "600") {
  Vcents = "60";
  } else 
  if(Vcents == "500") {
  Vcents = "50";
  } else 
  if(Vcents == "400") {
  Vcents = "40";
  } else 
  if(Vcents == "300") {
  Vcents = "30";
  } else
  if(Vcents == "200") {
  Vcents = "20";
  } else
  if(Vcents == "100") {
  Vcents = "10";
  } else {
  Vcents = Vcents;
  }

   
   var Vformat = "";

   if(Vnum >= 10000000) {
   Vformat = (V10million + "," + V1million + "" + V100thousand + "," + V10thousand + "" + V1thousand + "," + Vhundreds + "" + Vtens + "" + Vones + "." + Vcents);
   }
   else
   if(Vnum >= 1000000) {
   Vformat = (V1million + "" + V100thousand + "," + V10thousand + "" + V1thousand + "," + Vhundreds + "" + Vtens + "" + Vones + "." + Vcents);
   }
   else
   if(Vnum >= 100000) {
   Vformat = (V100thousand + "," + V10thousand + "" + V1thousand + "," + Vhundreds + "" + Vtens + "" + Vones + "." + Vcents);
   }
   else
   if(Vnum >= 10000) {
   Vformat = (V10thousand + "" + V1thousand + "," + Vhundreds + "" + Vtens + "" + Vones + "." + Vcents);
   }
   else
   if(Vnum >= 1000) {
   Vformat = (V1thousand + "," + Vhundreds + "" + Vtens + "" + Vones + "." + Vcents);
   }
   else
   if(Vnum >= 100) {
   Vformat = (Vhundreds + "" + Vtens + "" + Vones + "." + Vcents);
   }
   else
   if(Vnum >= 10) {
   Vformat = (Vtens + "" + Vones + "." + Vcents);
   }
   else
   if(Vnum >= 1) {
   Vformat = (Vones + "." + Vcents);
   } else {
   Vformat = ("0." + Vcents);
   }

  return Vformat;

  }
}


function checkNumber(input, min, max, msg)

{

    msg = msg + " field has invalid data: " + input.value;



    var str = input.value;

    for (var i = 0; i < str.length; i++) {

        var ch = str.substring(i, i + 1)

        if ((ch < "0" || "9" < ch) && ch != '.') {

            alert(msg);

            return false;

        }

    }

    var num = 0 + str

    if (num < min || max < num) {

        alert(msg + " not in range [" + min + ".." + max + "]");

        return false;

    }

    input.value = str;

    return true;

}



function computeField(input)

{

    if (input.value != null && input.value.length != 0)

        input.value = "" + eval(input.value);

    computeForm(input.form);

}



function computeForm(form,mq)

{

    if ((form.period.value == null || form.period.value.length == 0) ||

        (form.interest.value == null || form.interest.value.length == 0) ||

        (form.principal.value == null || form.principal.value.length == 0)) {

        return;

    }



    if (!checkNumber(form.period, 1, 120, "Period") ||

        !checkNumber(form.interest, .001, 99, "Interest") ||

        !checkNumber(form.principal, 100, 10000000, "Principal")) {

        form.payment.value = "Invalid";

        return;

    }


    if (form.period.value % 3 != 0) {

        form.period.value = "Invalid";
        return;

    }


    if (mq == "m") {	

    form.calcint.value = ""
    form.totalint.value = ""

    var Vpayment = (form.principal.value * form.interest.value) / (1200 + parseInt(form.interest.value) );
    var Vtotalint = Vpayment;

    form.calcint.value = "Rs. " + formatNum(Vpayment);


	for(s=1; s<parseInt(form.period.value); s++) { 

	    Vtotalint = Vtotalint + ( ((parseInt(form.principal.value) + Vtotalint)* form.interest.value) / (1200 + parseInt(form.interest.value)) ) ;

	}

		
    form.totalint.value = "Rs. " + formatNum(Vtotalint); } 



    if (mq == "q") {	

    form.calcint.value = ""
    form.totalint.value = ""

    var Vpayment = (form.principal.value * form.interest.value * 3) / (1200);
    form.calcint.value = "Rs. " + formatNum(Vpayment);

    var Vtotalint = Vpayment;

//    var Vtotalint = ( (form.principal.value * form.interest.value ) / (1200) )  * form.period.value;


	for(s=1; s<(parseInt(form.period.value)/3); s++) { 

	    Vtotalint = Vtotalint + ( (((parseInt(form.principal.value) + Vtotalint)* form.interest.value) * 3 ) / (1200 + parseInt(form.interest.value)) ) ;
	}

    form.totalint.value = "Rs. " + formatNum(Vtotalint);
	}
}



function clearForm(form)

{

    form.period.value = "";

    form.interest.value = "";

    form.principal.value = "";

    form.calcint.value = "";

    form.totalint.value = "";
}


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