program gen_be_cov3d
use da_control, only : stderr, stdout, filename_len
use da_tools_serial, only : da_get_unit,da_advance_cymdh
implicit none
character*10 :: start_date, end_date ! Starting and ending dates.
character*10 :: date, new_date ! Current date (ccyymmddhh).
character*10 :: variable1 ! Variable name
character*10 :: variable2 ! Variable name
character(len=filename_len) :: filename ! Input filename.
character*3 :: ce ! Member index -> character.
integer :: ni, nj, nk ! Grid dimensions.
integer :: i, j, k, member ! Loop counters.
integer :: b ! Bin marker.
integer :: sdate, cdate, edate ! Starting, current ending dates.
integer :: interval ! Period between dates (hours).
integer :: ne ! Number of ensemble members.
integer :: bin_type ! Type of bin to average over.
integer :: num_bins ! Number of bins (3D fields).
integer :: num_bins2d ! Number of bins (3D fields).
real :: lat_min, lat_max ! Used if bin_type = 2 (degrees).
real :: binwidth_lat ! Used if bin_type = 2 (degrees).
real :: hgt_min, hgt_max ! Used if bin_type = 2 (m).
real :: binwidth_hgt ! Used if bin_type = 2 (m).
real :: coeffa, coeffb ! Accumulating mean coefficients.
logical :: first_time ! True if first file.
real, allocatable :: field1(:,:,:) ! Field 1.
real, allocatable :: field2(:,:,:) ! Field 2.
integer, allocatable:: bin(:,:,:) ! Bin assigned to each 3D point.
integer, allocatable:: bin2d(:,:) ! Bin assigned to each 2D point.
integer, allocatable:: bin_pts(:) ! Number of points in bin (3D fields).
real, allocatable :: covar(:) ! Covariance between input fields.
real, allocatable :: var(:) ! Autocovariance of field.
namelist / gen_be_cov3d_nl / start_date, end_date, interval, &
ne, variable1, variable2
integer :: ounit,iunit,namelist_unit
stderr = 0
stdout = 6
!---------------------------------------------------------------------------------------------
write(6,'(a)')' [1] Initialize namelist variables and other scalars.'
!---------------------------------------------------------------------------------------------
call da_get_unit(ounit)
call da_get_unit(iunit)
call da_get_unit(namelist_unit)
start_date = '2004030312'
end_date = '2004033112'
interval = 24
ne = 1
variable1 = 'psi'
variable2 = 'chi'
open(unit=namelist_unit, file='gen_be_cov3d_nl.nl', &
form='formatted', status='old', action='read')
read(namelist_unit, gen_be_cov3d_nl)
close(namelist_unit)
read(start_date(1:10), fmt='(i10)')sdate
read(end_date(1:10), fmt='(i10)')edate
write(6,'(4a)')' Computing covariance for fields ', variable1 , ' and ', variable2
write(6,'(4a)') ' Time period is ', start_date, ' to ', end_date
write(6,'(a,i8,a)')' Interval between dates = ', interval, 'hours.'
write(6,'(a,i8)')' Number of ensemble members at each time = ', ne
date = start_date
cdate = sdate
!---------------------------------------------------------------------------------------------
write(6,'(2a)')' [2] Read fields, and calculate correlations'
!---------------------------------------------------------------------------------------------
first_time = .true.
do while ( cdate <= edate )
write(6,'(a,a)')' Processing data for date ', date
do member = 1, ne
write(ce,'(i3.3)')member
! Read first field:
filename = trim(variable1)//'/'//date(1:10)
filename = trim(filename)//'.'//trim(variable1)//'.e'//ce
open (iunit, file = filename, form='unformatted')
read(iunit)ni, nj, nk
if ( first_time ) then
write(6,'(a,3i8)')' i, j, k dimensions are ', ni, nj, nk
allocate( bin(1:ni,1:nj,1:nk) )
allocate( bin2d(1:ni,1:nj) )
allocate( field1(1:ni,1:nj,1:nk) )
allocate( field2(1:ni,1:nj,1:nk) )
! Read bin info:
filename = 'bin.data'
open (iunit+1, file = filename, form='unformatted')
read(iunit+1)bin_type
read(iunit+1)lat_min, lat_max, binwidth_lat
read(iunit+1)hgt_min, hgt_max, binwidth_hgt
read(iunit+1)num_bins, num_bins2d
read(iunit+1)bin(1:ni,1:nj,1:nk)
read(iunit+1)bin2d(1:ni,1:nj)
close(iunit+1)
allocate( bin_pts(1:num_bins) )
allocate( covar(1:num_bins) )
allocate( var(1:num_bins) )
bin_pts(:) = 0
covar(:) = 0.0
var(:) = 0.0
first_time = .false.
end if
read(iunit)field1
close(iunit)
! Read second field:
filename = trim(variable2)//'/'//date(1:10)
filename = trim(filename)//'.'//trim(variable2)//'.e'//ce
open (iunit, file = filename, form='unformatted')
read(iunit)ni, nj, nk
read(iunit)field2
close(iunit)
! Calculate covariances:
do k = 1, nk
do j = 1, nj
do i = 1, ni
b = bin(i,j,k)
bin_pts(b) = bin_pts(b) + 1
coeffa = 1.0 / real(bin_pts(b))
coeffb = real(bin_pts(b)-1) * coeffa
covar(b) = coeffb * covar(b) + coeffa * field1(i,j,k) * field2(i,j,k)
var(b) = coeffb * var(b) + coeffa * field2(i,j,k) * field2(i,j,k)
end do
end do
end do
end do ! End loop over ensemble members.
! Calculate next date:
call da_advance_cymdh( date, interval, new_date )
date = new_date
read(date(1:10), fmt='(i10)')cdate
end do ! End loop over times.
filename = trim(variable1)//'.'//trim(variable2)//'.dat'
open (ounit, file = filename, status='unknown')
do k = 1, nk
do j = 1, nj
do i = 1, ni
b = bin(i,j,k) ! Take value from center of i dimension.
if ( var(b) /= 0.0 ) then
write(ounit,'(f16.8)')covar(b) / var(b)
else
write(ounit,'(f16.8)')0.0
end if
end do
end do
end do
end program gen_be_cov3d