我的计算器函数不支持小数

function calculate(num1, num2, operator) {
    let result;
    switch (operator) {
        case '+':
            result = num1 + num2;
            break;
        case '-':
            result = num1 - num2;
            break;
        case '*':
            result = num1 * num2;
            break;
        case '/':
            if (num2 === 0) {
                throw new Error("Division by zero is not allowed.");
            }
            result = num1 / num2;
            break;
        default:
            throw new Error("Invalid operator.");
    }
    return result;
}

// 示例调用
console.log(calculate(10.5, 2.3, '+')); // 输出 12.8
console.log(calculate(10.5, 2.3, '-')); // 输出 8.2
console.log(calculate(10.5, 2.3, '*')); // 输出 24.15
console.log(calculate(10.5, 2.3, '/')); // 输出 4.565217391304348