/[lmdze]/trunk/dyn3d/conf_dat2d.f
ViewVC logotype

Annotation of /trunk/dyn3d/conf_dat2d.f

Parent Directory Parent Directory | Revision Log Revision Log


Revision 76 - (hide annotations)
Fri Nov 15 18:45:49 2013 UTC (10 years, 6 months ago) by guez
Original Path: trunk/dyn3d/conf_dat2d.f90
File size: 4158 byte(s)
Moved everything out of libf.
1 guez 3 module conf_dat2d_m
2    
3     IMPLICIT NONE
4    
5     contains
6    
7     SUBROUTINE conf_dat2d(xd, yd, xf, yf, champd, interbar)
8    
9 guez 68 ! From conf_dat2d.F, version 1.2 2006/01/27 15:14:22
10     ! Author : P. Le Van
11 guez 3
12     ! Ce sous-programme configure le champ de données 2D 'champd' et
13     ! les longitudes et latitudes de telle façon qu'on ait - pi à pi
14     ! en longitude et pi/2 à - pi/2 en latitude.
15    
16     ! This procedure receives a 2D field, with the corresponding
17     ! coordinate variables: longitude and latitude.
18     ! The procedure converts longitude and latitude to radians, if the
19     ! input values are in degrees.
20     ! If the input longitudes are between 0 and 2 pi, the procedure
21     ! computes the congruent longitudes between -pi and pi, and permutes
22     ! them so they stay in increasing order.
23     ! If the input latitudes are from south pole to north pole, the
24     ! procedure permutes them so they become from north to south.
25     ! Any change on longitudes or latitudes induces a change on the 2D field.
26     ! If required, the longitudes and latitudes are finally replaced
27     ! by their mid-values.
28    
29 guez 39 use nr_util, only: assert_eq, pi
30 guez 3
31     REAL, intent(in):: xd(:)
32     ! (longitudes, in degrees or radians, in increasing order, from 0°
33     ! to 360° or -180° to 180°)
34    
35     REAL, intent(in):: yd(:)
36     ! (latitudes, in degrees or radians, in increasing or decreasing
37     ! order, from pole to pole)
38    
39     LOGICAL, intent(in), optional:: interbar
40     REAL, intent(out):: xf(:), yf(:) ! longitudes and latitudes, in rad
41     REAL, intent(inout):: champd(:, :)
42    
43     ! Variables locales:
44    
45     INTEGER lons, lats
46     LOGICAL radianlon ! "xd" is in degrees
47     logical invlon ! "xd" contains longitudes between 0 and 2 pi
48     logical radianlat ! "yd" is in rad
49     REAL rlatmin, rlatmax, old_xf_1
50     INTEGER i, j
51     logical mid_values
52    
53     !------------------------------
54    
55     lons = assert_eq(size(xd), size(xf), size(champd, 1), "conf_dat2d lons")
56     lats = assert_eq(size(yd), size(yf), size(champd, 2), "conf_dat2d lats")
57    
58     IF (xd(1) >= - pi -0.5 .AND. xd(lons) <= pi + 0.5) THEN
59     radianlon = .TRUE.
60     invlon = .FALSE.
61     ELSE IF (xd(1) >= -0.5 .AND. xd(lons) <= 2 * pi+0.5) THEN
62     radianlon = .TRUE.
63     invlon = .TRUE.
64     ELSE IF (xd(1) >= -180.5 .AND. xd(lons) <= 180.5) THEN
65     radianlon = .FALSE.
66     invlon = .FALSE.
67     ELSE IF (xd(1) >= -0.5 .AND. xd(lons) <= 360.5) THEN
68     radianlon = .FALSE.
69     invlon = .TRUE.
70     ELSE
71     stop '"conf_dat2d": problem with longitudes'
72     ENDIF
73    
74     rlatmin = MIN(yd(1), yd(lats))
75     rlatmax = MAX(yd(1), yd(lats))
76    
77     IF (rlatmin >= -pi / 2 - 0.5 .AND. rlatmax <= pi / 2 + 0.5)THEN
78     radianlat = .TRUE.
79     ELSE IF (rlatmin >= -90. - 0.5 .AND. rlatmax <= 90. + 0.5) THEN
80     radianlat = .FALSE.
81     ELSE
82     stop '"conf_dat2d": problem with latitudes'
83     ENDIF
84    
85     IF (radianlon) THEN
86     xf(:) = xd(:)
87     else
88     xf(:) = xd(:) * pi / 180. ! convert to rad
89     ENDIF
90    
91     IF (radianlat) THEN
92     yf(:) = yd(:)
93     else
94     yf(:) = yd(:) * pi / 180. ! convert to rad
95     ENDIF
96    
97     IF (invlon) THEN
98     ! On tourne les longitudes pour avoir - pi à + pi :
99    
100     ! Get the index of the first longitude > pi:
101     i = 1
102     do while (xf(i) <= pi)
103     i = i + 1
104     end do
105    
106     xf(i:) = xf(i:) - 2 * pi
107     xf(:) = cshift(xf, shift=i - 1)
108     champd(:, :) = cshift(champd, shift=i - 1)
109     ENDIF
110    
111     IF (yd(1) < yd(lats)) THEN
112     ! "yd" contains latitudes from south pole to north pole,
113     ! reverse their order in "yf":
114     yf(lats:1:-1) = yf(:)
115     champd(:, lats:1:-1) = champd(:, :)
116     ENDIF
117    
118     if (present(interbar)) then
119     mid_values = interbar
120     else
121     mid_values = .true. ! default
122     end if
123     if (mid_values) then
124     ! Replace longitudes and latitudes by their mid-values:
125     old_xf_1 = xf(1)
126     forall (i = 1: lons - 1) xf(i) = 0.5 * (xf(i) + xf(i+1))
127     xf(lons) = 0.5 * (xf(lons) + old_xf_1 + 2 * pi)
128    
129     forall (j = 1: lats - 1) yf(j) = 0.5 * (yf(j) + yf(j+1))
130     end if
131    
132     END SUBROUTINE conf_dat2d
133    
134     end module conf_dat2d_m

  ViewVC Help
Powered by ViewVC 1.1.21