Javascript浮点数运算

Javascript

function add(a, b) {
    var c, d, e;
    try {
        c = a.toString().split(".")[1].length;
    } catch (f) {
        c = 0;
    }
    try {
        d = b.toString().split(".")[1].length;
    } catch (f) {
        d = 0;
    }
    return e = Math.pow(10, Math.max(c, d)), (mul(a, e) + mul(b, e)) / e;
}

function sub(a, b) {
    var c, d, e;
    try {
        c = a.toString().split(".")[1].length;
    } catch (f) {
        c = 0;
    }
    try {
        d = b.toString().split(".")[1].length;
    } catch (f) {
        d = 0;
    }
    return e = Math.pow(10, Math.max(c, d)), (mul(a, e) - mul(b, e)) / e;
}

function mul(a, b) {
    var c = 0,
        d = a.toString(),
        e = b.toString();
    try {
        c += d.split(".")[1].length;
    } catch (f) {}
    try {
        c += e.split(".")[1].length;
    } catch (f) {}
    return Number(d.replace(".", "")) * Number(e.replace(".", "")) / Math.pow(10, c);
}

function div(a, b) {
    var c, d, e = 0,
        f = 0;
    try {
        e = a.toString().split(".")[1].length;
    } catch (g) {}
    try {
        f = b.toString().split(".")[1].length;
    } catch (g) {}
    return c = Number(a.toString().replace(".", "")), d = Number(b.toString().replace(".", "")), mul(c / d, Math.pow(10, f - e));
}

Typescript

export class MathTool {
    static add(a: number, b: number) {
        let c, d, e;
        try {
            c = a.toString().split(".")[1].length;
        } catch (f) {
            c = 0;
        }
        try {
            d = b.toString().split(".")[1].length;
        } catch (f) {
            d = 0;
        }
        return e = Math.pow(10, Math.max(c, d)), (MathTool.mul(a, e) + MathTool.mul(b, e)) / e;
    }

    static sub(a: number, b: number) {
        let c, d, e;
        try {
            c = a.toString().split(".")[1].length;
        } catch (f) {
            c = 0;
        }
        try {
            d = b.toString().split(".")[1].length;
        } catch (f) {
            d = 0;
        }
        return e = Math.pow(10, Math.max(c, d)), (MathTool.mul(a, e) - MathTool.mul(b, e)) / e;
    }

    static mul(a: number, b: number) {
        let c = 0,
            d = a.toString(),
            e = b.toString();
        try {
            c += d.split(".")[1].length;
        } catch (f) { }
        try {
            c += e.split(".")[1].length;
        } catch (f) { }
        return Number(d.replace(".", "")) * Number(e.replace(".", "")) / Math.pow(10, c);
    }

    static div(a: number, b: number) {
        let c, d, e = 0,
            f = 0;
        try {
            e = a.toString().split(".")[1].length;
        } catch (g) { }
        try {
            f = b.toString().split(".")[1].length;
        } catch (g) { }
        return c = Number(a.toString().replace(".", "")), d = Number(b.toString().replace(".", "")), MathTool.mul(c / d, Math.pow(10, f - e));
    }
}