today = new Date();
today.setHours(0);
today.setMinutes(0);
today.setSeconds(0);
today.setMilliseconds(0)
yesterday = new Date();
yesterday.setTime(today.getTime()-24*3600*1000);

function debut_date_func(date, y, m, d) {
	if (date <= yesterday) return true;
	return false;
}

function fin_date_func(date, y, m, d) {
	var depart_date_str = document.getElementById('debut').value;
	if (depart_date_str == "") {
		var depart_date = yesterday;
	} else {
		depart_date_us = "";
		var depart_date = new Date();
		depart_date_us += depart_date_str.substring(3, 5)+"/";
		depart_date_us += depart_date_str.substring(0, 2)+"/";
		depart_date_us += depart_date_str.substring(6, 10);
		depart_date.setTime(Date.parse(depart_date_us));
	}
	if (date < depart_date)
		return true;
	else
		return false;
}