function myFunction_left() {
       var radios = document.querySelectorAll('input[type=radio]');

        for (i = 0; i < radios.length; ++i) {
            var radio = radios[i];
            if (radio.value == 'left' && radio.checked) {
                $('#load_switching_point').val(radio.dataset.amount);
                break;
            } else {
                $('#load_switching_point').val(9999);
            }
        }
};