!*==calcwu.spg  processed by SPAG 6.70Rc at 15:33 on 10 Dec 2012
!*------------------   SPAG Configuration Options   --------------------
!*--0323,76 000101,-1 000000102011332010100002000000210211210,136 10 --
!*--1100000011112111000000000000,10,10,10,10,10,10,900,100 200000000 --
!*--000000010000000000000,72,72 73,42,38,33 00011112110000100000000  --
!*----------------------------------------------------------------------
 
!$Author: joelevin $
!$Date: 2011-03-24 11:33:26 -0500 (Thu, 24 Mar 2011) $
!$Revision: 11724 $
!$HeadURL: https://eweru-dev1.eweru.ksu.edu/svn/code/weps1/branches/WEPS_F90_update/weps.src/src/lib_erosion/calcwu.for $
 
      subroutine calcwu
      use i_p1unconv
      use i_p1const
      use i_p1werm
      use i_wpath
      use i_m1sim
      use i_m1flag
      use i_w1wind
      use i_file
      use i_main
      use s_caldatw
      use s_exit
      use s_julday
      implicit none
!*--CALCWU27
!
!*** Start of declarations rewritten by SPAG
!
! Local variables
!
      integer :: day,i,jd,month,year
      logical :: fexist
      character(80) :: line
!
!*** End of declarations rewritten by SPAG
!
 
!     + + + PURPOSE + + +
!    This subroutine reads sub-daily wind speeds from a user supplied
!    file or simulates the sub-daily wind speeds if the file is not
!    supplied.
 
!    programmer: John Tatarko
!    version: 07/28/92
 
!     Edit History
!     07-Mar-99   wjr   changed unit 8 to luiwsd
 
!     + + + KEY WORDS + + +
!     wind speed, wind direction, sub-daily wind speed
 
!     + + + GLOBAL COMMON BLOCKS + + +
 
 
!     + + + LOCAL COMMON BLOCKS + + +
 
!     + + + LOCAL VARIABLES + + +
 
 
 
!      real    large,
!     r        small
 
!     + + + LOCAL DEFINITIONS + + +
 
!   i         - Index on subdaily loop (i=1,ntstep)
!   day       - The current day in the sub-daily wind file.
!   month     - The current month in the sub-daily wind file.
!   year      - The current year in the sub-daily wind file.
!   large     - Variable initialized with small value so that MAX
!               intrinsic function may find the maximum windspeed.
!   line      - This character variable is used to read the header
!               information in the file.
!   small     - Variable initialized with large value so that MIN
!               intrinsic function may find the minimum windspeed.
!   subfil    - This variable holds the subdaily wind information
!               file name.
!   subflg    - This logical variable is a flag to read header
!               information in the sub-daily wind file
!               (if .true., read header; if .false., skip).
 
!     + + + FUNCTIONS CALLED + + +
 
!     + + + FUNCTION DEFINITIONS + + +
!     julday  -  Calculates the julian date given the day, month, year
 
!     + + + OUTPUT FORMATS + + +
 1000 format (2I2,2x,i4,1x,f6.1,24F6.2)
 1100 format (/,' using subdaily wind file:  ',a80)
 1200 format (/,' error reading subdaily wind file: ',a80)
 1300 format (/,' no subdaily wind in file for',2I3,1x,i4,              &
     &' - it will be&                                                   &
     &             generated')
 
!     + + + END SPECIFICATIONS + + +
 
!     + + + INITIALIZATION + + +
 
!      small = 1e20
!      large = -1e20
 
!    if 'real' sub-daily data exixts - read it
      if (am0efl>0) open (unit=24,file=rootp(1:len_trim(rootp))         &
                         &//'subday.out')
      inquire (file=subfil,exist=fexist)
      if (fexist) then
         write (*,1100) subfil
         if (.NOT.(subflg.EQV..FALSE.)) then
            do
               read (luiwsd,'(a)') line
               if (line(1:1)/='#') then
                  backspace (unit=luiwsd)
                  subflg = .FALSE.
                  exit
               end if
            end do
         end if
         read (luiwsd,*,end=10,err=30) day,month,year,awadir,           &
                                     & &(awu(i),i=1,ntstep)
 
!        test for current date
!        write (*,*) 'julday',day, month,year
         jd = julday(day,month,year)
         if (jd/=am0jd) then
            write (*,1300)
            go to 20
         end if
 
!        find max, min, and avg
!         do 40 i = 1, ntstep
!            large = max(large, awu(i))
!            small = min(small, awu(i))
!   40    continue
!         awudmx = large
!         awudmn = small
!         awudav = (awudmx + awudmn) / 2.
 
         go to 50
 10      backspace (unit=luiwsd)
      end if
 
!     if 'real' data does not exist - generate (for original wind_gen data only)
 20   if (wind_gen_fmt_flag==1) then     ! original wind_gen file format
         do i = 1,ntstep
            awu(i) = awudav + 0.5*(awudmx-awudmn)                       &
                   & *cos(2.*pi*&((ntstep*24)/ntstep-awhrmx+i)/ntstep)
         end do
         !awu(i) array should already be populated
      else if (ntstep/=24) then
         write (0,*) 'ntstep not equal to 24 - code changes needed!'
         go to 40
      end if
      go to 50
 
!     if error reading sub-daily file
 30   write (0,1200) subfil
 40   call exit(1)
! 500 stop
 
 50   call caldatw(day,month,year)
      if (am0efl>0) write (24,1000) day,month,year,awadir,              &
                                  & (awu(i),i=1,ntstep)
 
      end subroutine calcwu