// 小数乘 ***
    accMul(arg1, arg2) {
        let 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)).toFixed(2)
        );
    };