# wkday --- get day-of-week corresponding to month,day,year

   integer function wkday (month, day, year)
   integer month, day, year

   integer lmonth, lday, lyear

   lmonth = month - 2
   lday = day
   lyear = year

   if (lmonth <= 0) {
      lmonth += 12
      lyear -= 1
      }

   wkday = mod (lday + (26 * lmonth - 2) / 10 + lyear + lyear / 4 - 34,
       7) + 1
   if (wkday < 1)       # correct for the Fortran mod function
      wkday += 7

   return
   end
