function mjd=date2mjd(year,month,day,hh,min,sec)

if month<=2
   month=month+12;
   year=year-1;
end

if (10000*year+100*month+day<=15821004)       %4.10.1582
   B=-2+fix((year+4716)/4)-1179;              % Julian calendar
else
   B=fix(year/400)-fix(year/100)+fix(year/4); % Gregorian calendar
end

MJD_midnight=365*year-679004+B+fix(30.6001*(month+1))+day;
part_of_day=(hh+min/60.0+sec/3600.0)/24.0;

mjd=MJD_midnight+part_of_day;