subroutine get_dayofmonth(year, month, doy, dom)

c-----------------------------------------------------------------------------------
c Description: Calculatie day of month (1-31) given month (1-12).
c
c Input parameters:
c year                year (yyyy)
c month               month (1-12)
c doy                 day of year (1-366)
c
c Output parameters:
c dom                 day of month (1-31)
c
c Revision history:
c                     01/14       R. Frey        Original version
c
c Calls
c                     None
c
c-----------------------------------------------------------------------------------

      IMPLICIT NONE

c-----------------------------------------------------------------------------------

c     Arguments.
      integer year, month, doy, dom

      character*160 errmsg
      integer bday(12), leap_bday(12), beg_day, il, im, j, status, level
      logical leap_year

c-----------------------------------------------------------------------------------

      data bday /1, 32, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335/
      data leap_bday /1, 32, 61, 92, 122, 153, 183, 214, 245, 275, 306, 336/

c-----------------------------------------------------------------------------------

c     Determine if leap year.
      il = mod(year, 4)
      if(il .eq. 0) then
        leap_year = .true.
      else
        leap_year = .false.
      end if

c-----------------------------------------------------------------------------------

c     Check value of month ('month').
      if(month .le. 0 .or. month .gt. 12) then
        level = 3
        status = -1
        write( errmsg,'(''Invalid month: '',i10)') month
            call message( 'get_dayofmonth', errmsg,
     &           status, level )
      end if

c-----------------------------------------------------------------------------------

c     Check day of year ('doy') value.
      if(doy .le. 0 .or. ( (.not. leap_year) .and. doy .gt. 365) .or.
     *  (leap_year .and. doy .gt. 366) ) then
        level = 3
        status = -1
        write( errmsg,'(''Invalid day of year: '',i10)') doy
            call message( 'get_month', errmsg,
     &           status, level )
      end if

c-----------------------------------------------------------------------------------

c     Find day of month (1-31).

      if(leap_year) then
        beg_day = leap_bday(month)
      else
        beg_day = bday(month)
      end if

      dom = (doy - beg_day) + 1

c-----------------------------------------------------------------------------------

      return
      end

c-----------------------------------------------------------------------------------