function put_commas(input)
    {var result, len;
  input += "";
    len = input.indexOf(".");
    if(len == -1) {len = input.length; result = "";}
    else {result = input.substring(len, input.length);}
    while(len > 3) {result = input.substring(len-3, len) + result; result = "," + result; len -= 3;}
    result = input.substring(0, len) + result; return result;}

function strip_commas(input) {var newnum; var ch; newnum ="";
        for(var i=0; i<input.length; i++)
              {ch = input.charAt(i); if(ch != ",")
                 {newnum += ch;}}
        return parseFloat(newnum);}

function checkNum(input)
    {var oldnum; var newnum; var ch; oldnum = input.value; newnum ="";
  for(var i=0; i<oldnum.length; i++)
          {ch = oldnum.charAt(i); if(ch != ",")
                {newnum += ch;}}
  return parseFloat(newnum);}

function checkNumPeriods(input)
     {input.value = checkNum(input);
  input.value = parseInt(input.value);
  if(input.value == null ||          
         input.value.length == 0 ||
            input.value == "NaN")
           {input.value = "";}
  else {if(parseFloat(input.value) <= 0)
                 {input.value = "";}}
  calcTotal(input.form);
  input.value = put_commas(input.value);}

function checkPayment(input)
     {input.value = checkNum(input);
  input.value = parseFloat(input.value);
  if(input.value == null ||          
         input.value.length == 0 ||
     input.value == "NaN")
           {input.value = "";}
  else {if(parseFloat(input.value) < 0)
                 {input.value = "";}}
  calcTotal(input.form);
  input.value = put_commas(input.value);}

function checkInterest(input)
     {input.value = parseFloat(input.value);
  if(input.value == null ||          
         input.value.length == 0 ||
     input.value == "NaN")
           {input.value = "";}
  else {if(parseFloat(input.value) <= 0 || 
       parseFloat(input.value) > 100.0)
                 {input.value = "";}}
  calcTotal(input.form);}
function calcTotal(input) {
         var fee=350;
         if(input.interest.value == "" || 
     input.nper.value == "" ||
     input.pmt.value == "") {
    input.total.value = "";}
  else {i = 0.17;
    i = i / 12;
    
    n = .5 * 12;
    tmp = (1/i) * (1 - Math.pow(1/(1+i), n))* 4.33;
    tmp = strip_commas(input.pmt.value) * tmp;
    tmp = (Math.round(tmp*100) / 100)-fee*1;
    tmp=(tmp>0)?tmp:0;
    input.total.value = put_commas(tmp);
    
    n = 1 * 12;
    tmp1 = (1/i) * (1 - Math.pow(1/(1+i), n))* 4.33;
    tmp1 = strip_commas(input.pmt.value) * tmp1;
    tmp1 = (Math.round(tmp1*100) / 100)-fee*1;
    tmp1=(tmp1>0)?tmp1:0;
    input.total1.value = put_commas(tmp1);

    n = 2 * 12;
    tmp2 = (1/i) * (1 - Math.pow(1/(1+i), n))* 4.33;
    tmp2 = strip_commas(input.pmt.value) * tmp2;
    tmp2 = (Math.round(tmp2*100) / 100)-fee*1;
    tmp2=(tmp2>0)?tmp2:0;
    input.total2.value = put_commas(tmp2);

    n = 3 * 12;
    tmp3 = (1/i) * (1 - Math.pow(1/(1+i), n))* 4.33;
    tmp3 = strip_commas(input.pmt.value) * tmp3;
    tmp3 = (Math.round(tmp3*100) / 100)-fee*1;
    tmp3=(tmp3>0)?tmp3:0;
    input.total3.value = put_commas(tmp3);    

    n = 4 * 12;
    tmp4 = (1/i) * (1 - Math.pow(1/(1+i), n))* 4.33;
    tmp4 = strip_commas(input.pmt.value) * tmp4;
    tmp4 = (Math.round(tmp4*100) / 100)-fee*1;
    tmp4=(tmp4>0)?tmp4:0;
    input.total4.value = put_commas(tmp4);  

    n = 5 * 12;
    tmp5 = (1/i) * (1 - Math.pow(1/(1+i), n))* 4.33;
    tmp5 = strip_commas(input.pmt.value) * tmp5;
    tmp5 = (Math.round(tmp5*100) / 100)-fee*1;
    tmp5=(tmp5>0)?tmp5:0;
    input.total5.value = put_commas(tmp5);  
      }
}