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JS 關於小數的精確計算

//js 加法計算
//呼叫:accAdd(arg1,arg2)
//返回值:arg1加arg2的精確結果
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 ((arg1*m+arg2*m)/m).toFixed(2);
}
//js 減法計算
//呼叫:Subtr(arg1,arg2)
//返回值:arg1減arg2的精確結果
function Subtr(arg1,arg2){
var r1,r2,m,n;
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));
//last modify by deeka
//動態控制精度長度
n=(r1>=r2)?r1:r2;
return ((arg1*m-arg2*m)/m).toFixed(2);
}
//js 除法函式
//呼叫:accDiv(arg1,arg2)
//返回值:arg1除以arg2的精確結果
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);
}
}

//js 乘法函式
//呼叫:accMul(arg1,arg2)
//返回值:arg1乘以arg2的精確結果
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)
}