In JavaScript, when you use decimals for addition, subtraction, multiplication and division, you will find that the results are sometimes followed by a long period of decimals, which complicates the operation and affects the calculation results. I looked up the reasons online and found the following: In JavaScript, there are always many decimal places when calculating data with decimals. This is because the calculation of floating point numbers in JavaScript is based on binary calculations.
/**
* Addition operation to avoid multiple digits and calculation accuracy loss after the decimal point is added to the data.
*
* @param num1 addend 1 | num2 addend 2
*/
function numAdd(num1, num2) {
var baseNum, baseNum1, baseNum2;
try {
baseNum1 = num1.toString().split(".")[1].length;
} catch (e) {
baseNum1 = 0;
}
try {
baseNum2 = num2.toString().split(".")[1].length;
} catch (e ) {
baseNum2 = 0;
}
baseNum = Math.pow(10, Math.max(baseNum1, baseNum2));
return (num1 * baseNum num2 * baseNum) / baseNum;
};
/**
* Addition operation to avoid multiple digits and calculation accuracy loss after adding decimal point of data.
*
* @param num1 minuend | num2 minuend
*/
function numSub(num1, num2) {
var baseNum, baseNum1, baseNum2;
var precision;// precision
try {
baseNum1 = num1.toString().split(".")[1].length;
} catch (e) {
baseNum1 = 0;
}
try {
baseNum2 = num2.toString().split(".")[1].length;
} catch (e) {
baseNum2 = 0;
}
baseNum = Math.pow( 10, Math.max(baseNum1, baseNum2));
precision = (baseNum1 >= baseNum2) ? baseNum1 : baseNum2;
return ((num1 * baseNum - num2 * baseNum) / baseNum).toFixed(precision );
};
/**
* Multiplication operation to avoid multiple digits and loss of calculation accuracy after multiplying data with decimal point.
*
* @param num1 multiplicand | num2 multiplier
*/
function numMulti(num1, num2) {
var baseNum = 0;
try {
baseNum = num1.toString ().split(".")[1].length;
} catch (e) {
}
try {
baseNum = num2.toString().split(".") [1].length;
} catch (e) {
}
return Number(num1.toString().replace(".", "")) * Number(num2.toString(). replace(".", "")) / Math.pow(10, baseNum);
};
/**
* Division operation to avoid multiple digits and calculation accuracy loss after data is divided by decimal point.
*
* @param num1 dividend | num2 divisor
*/
function numDiv(num1, num2) {
var baseNum1 = 0, baseNum2 = 0;
var baseNum3, baseNum4;
try {
baseNum1 = num1.toString().split(".")[1].length;
} catch (e) {
baseNum1 = 0;
}
try {
baseNum2 = num2.toString().split(".")[1].length;
} catch (e ) {
baseNum2 = 0;
}
with (Math) {
baseNum3 = Number(num1.toString().replace(".", ""));
baseNum4 = Number(num2.toString().replace(".", ""));
return (baseNum3 / baseNum4) * pow(10, baseNum2 - baseNum1);
}
};