da_get_reglats.inc

1 subroutine da_get_reglats( nj, lat, sinlat, coslat, int_wgts)
2 
3    !-----------------------------------------------------------------------
4    ! Purpose: TBD
5    !-----------------------------------------------------------------------
6 
7    implicit none
8 
9    integer, intent(in)  :: nj             ! Number of latitudes
10    real,    intent(out) :: lat(1:nj)      ! Latitude(radians, from south).
11    real,    intent(out) :: sinlat(1:nj)   ! sin(Latitude).
12    real,    intent(out) :: coslat(1:nj)   ! cos(Latitude).
13    real,    intent(out) :: int_wgts(1:nj) ! Legendre Integration weights. 
14 
15    integer :: j              ! Loop counter.
16    real    :: delta_phi      ! Regular latitude interval.
17 
18    if (trace_use) call da_trace_entry("da_get_reglats")
19 
20    delta_phi = pi / real(nj-1) 
21 
22    do j = 1, nj / 2
23       lat(j) = -0.5 * pi + delta_phi * real(j - 1)
24       sinlat(j) = sin(lat(j))
25       coslat(j) = cos(lat(j))
26       int_wgts(j) = coslat(j) * delta_phi
27 
28       ! use symmetry for northern hemisphere:
29       lat(nj+1-j) = -lat(j)
30       sinlat(nj+1-j) = -sinlat(j)
31       coslat(nj+1-j) = coslat(j)
32       int_wgts(nj+1-j) = int_wgts(j)
33    end do
34 
35    if ((nj+1) / 2 == nj/2 + 1) then  ! Odd, then equator point:
36       lat(nj/2+1) = 0.0
37       sinlat(nj/2+1) = 0.0
38       coslat(nj/2+1) = 1.0
39       int_wgts(nj/2+1) = delta_phi
40    end if
41 
42    if (trace_use) call da_trace_exit("da_get_reglats")
43 
44 end subroutine da_get_reglats
45 
46