anchor.diff:              day = floor(day_fraction - this%month_start(month))+1
               year=year+this%year_zero
               
  +        !------------------------------------------------------------
  +        !
  +        ! Calculate the dates for a 360-day Calendar
  +        !
  +        !------------------------------------------------------------
           else if (this%calendar==THREESIXTY) then
               year=floor(mjd/360)
               day_fraction=mjd - year*360+1
  
positive.code:         second = nint((day_fraction-(24d0*60*1d-5))*60)
          
      end subroutine calendar_date
  
      !>------------------------------------------------------------
      !!  Return the day of the year corresponding to the current date_time
  
negative.code:             month = mod(h/s+m,n)+1
              year  = e/p-y+(n+m-month)/n
                          
          !------------------------------------------------------------
          !
          ! Calculate the dates for a No leap Calendar
          !
          !------------------------------------------------------------
          else if (this%calendar==NOLEAP) then
              year=floor(mjd/365)
              day_fraction=mjd - year*365+1
  