Js calculation precision problem

Simple floating-point arithmetic

parseFloat((mathematical expression).tofixed (digits));// toFixed() must run between 0 and 20
parseFloat((1.0 - 0.9).toFixed(10)) // Result is 0.1
parseFloat((0.3 / 0.1).toFixed(10)) // The result is 3
parseFloat((9.7 * 100).toFixed(10)) // Result is 970
parseFloat((2.22 + 0.1).toFixed(10)) // Result is 2.32
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The above method is not compatible with older versions of IE(6, 7, 8), and the return value of toFixed() method may not be accurate.

1. Precision processing of multiplication

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);
},
const num = this.accMul(arg1,100) // Call the handler method, where *100 handles the price
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2. Division precision processing

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); }}const num = this.accMul(arg1,arg2) // Call the processing method
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3. Accuracy processing of addition

accAdd(arg1, arg2) {
    var r1, r2, m, c;
    try {
        r1 = arg1.toString().split(".") [1].length;
    }
    catch (e) {
        r1 = 0;
    }
    try {
        r2 = arg2.toString().split(".") [1].length;
    }
    catch (e) {
        r2 = 0;
    }
    c = Math.abs(r1 - r2);
    m = Math.pow(10.Math.max(r1, r2));
    if (c > 0) {
        var cm = Math.pow(10, c);
        if (r1 > r2) {
            arg1 = Number(arg1.toString().replace(".".""));
            arg2 = Number(arg2.toString().replace("."."")) * cm;
        } else {
            arg1 = Number(arg1.toString().replace("."."")) * cm;
            arg2 = Number(arg2.toString().replace("."."")); }}else {
        arg1 = Number(arg1.toString().replace(".".""));
        arg2 = Number(arg2.toString().replace(".".""));
    }
    return (arg1 + arg2) / m;
}
const num = this.accMul(arg1,arg2) // Call the processing method
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4. Subtraction precision processing

accSub(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 //
    n = (r1 >= r2) ? r1 : r2;
    return ((arg1 * m - arg2 * m) / m).toFixed(n);
}
const num = this.accMul(arg1,arg2) // Call the processing method
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