많이 질문하고 많은시간 투자해서 이제 계산방법은 좀 터득했는데 콤마가 않찍히내요........
고수님들 좀도와주세요......................................

<form name="fwrite" method="post" action="javascript:fwrite_check(document.fwrite);" enctype="multipart/form-data" style="margin:0px;">
<input type=hidden name=null>
<input type=hidden name=w        value="<?=$w?>">
<input type=hidden name=bo_table value="<?=$bo_table?>">
<input type=hidden name=wr_id    value="<?=$wr_id?>">
<input type=hidden name=sca      value="<?=$sca?>">
<input type=hidden name=sfl      value="<?=$sfl?>">
<input type=hidden name=stx      value="<?=$stx?>">
<input type=hidden name=spt      value="<?=$spt?>">
<input type=hidden name=sst      value="<?=$sst?>">
<input type=hidden name=sod      value="<?=$sod?>">
<input type=hidden name=page     value="<?=$page?>">

<tr><td>
수량
<input type=text name="wr_11" id="a" value="0<?=$write[wr_11]?>" itemname="a" onKeyUp="my_calc(this.form)" style="text-align:right;" size="5" class="border" />
가격
<input type=text name="wr_12" id="a_a" value="0<?=$write[wr_12]?>" itemname="a_a" onKeyUp="my_calc(this.form)" style="text-align:right;" size="7"  onkeypress=Numberchk() class="border"/>
공급가
<input type=text name="wr_13" id="a_aa" value="0<?=$write[wr_13]?>" itemname="a_aa" style="text-align:right;" size=10 readonly class="no_border2" />
부가세
<input type=text name="wr_14" id="a_bat" value="0<?=$write[wr_14]?>" itemname="a_bat" style="text-align:right;" size=10 readonly class="no_border2"/>
운송비
<input type=text name="wr_15" id="a_aaa" value="0<?=$write[wr_15]?>" itemname="a_aaa" onKeyUp="my_calc(this.form)" style="text-align:right;" size="10" class="border" />
합계
<input type=text name="wr_16" id="a_sum" value="0<?=$write[wr_16]?>" itemname="a_sum" style="text-align:right;" size=10 readonly class="no_border" />
<br />
전체 합계:
<input type=text name="wr_23" id="total" value="0<?=$write[wr_23]?>" itemname="total" style="text-align:right;" size=10 readonly /></td>
</td></tr>
<script language="javascript">
  function my_calc(f){
  if(f.a.value=="")  f.a.value="0"; 
  f.a_aa.value = eval(f.a.value) * eval(f.a_a.value) ;
  f.a_bat.value = eval(f.a.value) * eval(f.a_a.value) * 0.1 ;
  f.a_sum.value = eval(f.a_aa.value) + eval(f.a_bat.value)  + eval(f.a_aaa.value) ; 
 my_total();
 }
 function my_total(){
 var f = document.fwrite;
  f.total.value = eval(f.a_sum.value) ;
  }
</script>
</form>