js about precise calculation and numerical formatting and direct reference to js files_javascript skills

(function () {
var calc = {
/*
Function, addition function, used to get accurate addition results
Note: The addition result of JavaScript will have errors , it will be more obvious when adding two floating point numbers. This function returns a more accurate addition result.
Parameters: arg1: the first addend; arg2 the second addend; d the number of decimal places to be retained. (This parameter does not need to be passed, otherwise the number of decimal places will not be processed)
Call: Calc.Add(arg1,arg2,d)
Return value: The result of adding two numbers
*/
Add: function (arg1, arg2,d) {
arg1 = arg1.toString(), arg2 = arg2.toString();
var arg1Arr = arg1.split("."), arg2Arr = arg2 .split("."), d1 = arg1Arr.length == 2 ? arg1Arr[1] : "", d2 = arg2Arr.length == 2 ? arg2Arr[1] : "";
var maxLen = Math. max(d1.length, d2.length);
var m = Math.pow(10, maxLen);
var result = Number(((arg1 * m arg2 * m) / m).toFixed(maxLen ));
var d = arguments[2];
return typeof d === "number" ? Number((result).toFixed(d)) : result;
},
/ *
Function: subtraction function, used to obtain accurate subtraction results
Description: The function returns a more accurate subtraction result.
Parameters: arg1: the first addend; arg2 the second addend; d. The number of decimal places to be retained (you can not pass this parameter, if not, the number of decimal places will not be processed
Call: Calc.Sub(arg1,arg2)
Return value: the result of subtracting two numbers
*/
Sub: function (arg1, arg2) {
return Calc.Add(arg1, -Number(arg2), arguments[2]);
},
/*
function : Multiplication function, used to obtain accurate multiplication results
Description: The function returns more accurate multiplication results.
Parameters: arg1: the first multiplier; arg2 the second multiplier; the number of decimal places to be retained in d (you can not pass this parameter, if not, the number of decimal places will not be processed)
Call: Calc .Mul(arg1,arg2)
Return value: the result of multiplying two numbers
*/
Mul: function (arg1, arg2) {
var r1 = arg1.toString(), r2 = arg2.toString(), m, resultVal, d = arguments[2];
m = (r1.split(".")[1] ? r1.split(".")[1].length : 0 ) (r2.split(".")[1] ? r2.split(".")[1].length : 0);
resultVal = Number(r1.replace(".", "")) * Number(r2.replace(".", "")) / Math.pow(10, m);
return typeof d !== "number" ? Number(resultVal) : Number(resultVal.toFixed(parseInt (d)));
},
/*
Function: division function, used to obtain accurate division results
Description: The function returns a more accurate division result.
Parameters: arg1: divisor; arg2 dividend; the number of decimal places to be retained in d (you can not pass this parameter, if not, the number of decimal places will not be processed)
Call: Calc.Div(arg1,arg2)
Return value: the result of dividing arg1 by arg2
*/
Div: function (arg1, arg2) {
var r1 = arg1.toString(), r2 = arg2.toString(), m, resultVal, d = arguments[2];
m = (r2.split(".")[1] ? r2.split(".")[1].length : 0) - (r1.split(" .")[1] ? r1.split(".")[1].length : 0);
resultVal = Number(r1.replace(".", "")) / Number(r2.replace( ".", "")) * Math.pow(10, m);
return typeof d !== "number" ? Number(resultVal) : Number(resultVal.toFixed(parseInt(d)));
},
/*
Round the value and format it.
@param num value (Number or String)
@param cent decimal place to be retained (Number)
@param isThousand Whether thousandths is required 0: Not required, 1: Required (numeric type);
@return Format string, such as '1,234,567.45'
@type String
Call: Calc.FormatNumber(num, cent,isThousand)
*/
FormatNumber: function formatNumber(num,cent,isThousand){
num = num.toString().replace(/$|,/g,'');
if(isNaN(num))//Check that the incoming value is a numeric type.
num = "0";
if(isNaN(cent))//Ensure that the incoming decimal place is a numeric value.
cent = 0;
cent = parseInt(cent);
cent = Math.abs(cent);//Find the number of decimal places and make sure it is a positive integer.
if(isNaN(isThousand) )//Make sure whether the thousandth place passed in is a numeric type.
isThousand = 0;
isThousand = parseInt(isThousand);
if(isThousand < 0)
isThousand = 0;
if(isThousand >=1) //Make sure the value passed in is only 0 or 1
isThousand = 1;
sign = (num == (num = Math.abs(num))); //Get the sign (positive/negative number)
//Math.floor: Return the largest integer less than or equal to its numerical parameter
num = Math.floor(num*Math.pow(10,cent) 0.50000000001);/ /Convert the specified decimal places to integers first. Round off the extra decimal places.
cents = num%Math.pow(10,cent); //Find the decimal place value.
num = Math.floor( num/Math.pow(10,cent)).toString();//Find the value of the integer digits.
cents = cents.toString();//Convert the decimal digits into a string to find the length of the decimal digits .
while(cents.lengthcents = "0" cents;
}
if(isThousand == 0) // No thousandth place character is required.
return (((sign)?'':'-') num '.' cents);
//Format the integer part in the thousandth place.
for (var i = 0; i < Math.floor((num.length-(1 i))/3); i )
num = num.substring(0,num.length-(4*i 3) ) ','
num.substring(num.length-(4*i 3));
return (((sign)?'':'-') num '.' cents);
}
};
window.Calc = calc;
}());