updated top-level README and version_decl for V4.5 (#1847)
[WRF.git] / var / da / da_radiance / init_constants_derived.inc
blob1d68534df525c558a1dd355a6dec31874657b1d3
1   subroutine init_constants_derived
2 !$$$  subprogram documentation block
3 !                .      .    .                                       .
4 ! subprogram:    init_constants_derived          set derived constants
5 !     prgmmr:    treadon          org: np23           date: 2004-12-02
7 ! abstract:  This routine sets derived constants
9 ! program history log:
10 !   2004-12-02  treadon
11 !   2005-03-03  treadon - add implicit none
13 !   input argument list:
15 !   output argument list:
17 ! attributes:
18 !   language: f90
19 !   machine:  ibm rs/6000 sp
21 !$$$
22     implicit none
24 !   Trigonometric constants
25     pi      = acos(-one)
26     deg2rad = pi/180.0_r_kind
27     rad2deg = one/deg2rad
28     tiny_r_kind = tiny(zero)
29     huge_r_kind = huge(zero)
30     tiny_single = tiny(zero_single)
31     huge_single = huge(zero_single)
33 !   Geophysical parameters used in conversion of geopotential to
34 !   geometric height
35     eccentricity_linear = sqrt(semi_major_axis**2 - semi_minor_axis**2)
36     eccentricity = eccentricity_linear / semi_major_axis
38     return
39   end subroutine init_constants_derived