function accAdd(arg1,arg2){ 
    var r1,r2,m;
    try{r1=arg1.toString().split(".")[1].length}catch(e){r1=0}
    try{r2=arg2.toString().split(".")[1].length}catch(e){r2=0}
    m=Math.pow(10,Math.max(r1,r2));
    return (accMul(arg1,m)+accMul(arg2,m))/m; 
}

/*
* 精确乘法
*/
function accMul(arg1,arg2){ 
    var m=0,s1=arg1.toString(),s2=arg2.toString(); 
    try{m+=s1.split(".")[1].length}catch(e){} 
    try{m+=s2.split(".")[1].length}catch(e){} 
    return Number(s1.replace(".",""))*Number(s2.replace(".",""))/Math.pow(10,m) 
}

/*
* 精确除法
*/
function accDiv(arg1,arg2){ 
    var t1=0,t2=0,r1,r2; 
    try{t1=arg1.toString().split(".")[1].length}catch(e){} 
    try{t2=arg2.toString().split(".")[1].length}catch(e){} 
    with(Math){ 
      r1=Number(arg1.toString().replace(".","")) 
      r2=Number(arg2.toString().replace(".","")) 
      return (r1/r2)*pow(10,t2-t1); 
    } 
}