doc-doxygen/html/pmesh_8f_source.html

00001       SUBROUTINE pmesh (kx, ky, px, py, kngx, kngy, cdper, kper,
00002      $                  pxi, pxs, pyi, pys)
00003 C****
00004 C               *****************************
00005 C               * OASIS ROUTINE  -  LEVEL 3 *
00006 C               * -------------     ------- *
00007 C               *****************************
00008 C
00009 C**** *pmesh* -  Calculate the mesh controlled by one point on a
00010 C               periodical or non-periodical grid.
00011 C
00012 C     Purpose:
00013 C     -------
00014 C     For one point defined by the coordinates (px(k),py(k))
00015 C     on a lat-lon grid, gives the inferior and superior longitudes
00016 C     (pxi,pxs) and latitudes (pyi,pys) of the associated mesh.
00017 C
00018 C
00019 C**   Interface:
00020 C     ---------
00021 C       *CALL*  *pmesh(kx, ky, px, py, kngx, kngy, cdper, kper,
00022 C                      pxi, pxs, pyi, pys)*
00023 C
00024 C     Input:
00025 C     -----
00026 C                kx    : point longitude index
00027 C                ky    : point latitude index
00028 C                px    : longitude array (real 2D)
00029 C                py    : latitude array (real 2D)
00030 C                kngx  : number of longitudes
00031 C                kngy  : number of latitudes
00032 C                cdper : grid periodicity
00033 C                kper  : number of overlapped points
00034 C
00035 C     Output:
00036 C     ------
00037 C                pxi  : inferior longitude
00038 C                pxs  : superior longitude
00039 C                pyi  : inferior latitude
00040 C                pys  : superior latitude
00041 C
00042 C     Workspace:
00043 C     ---------
00044 C     None
00045 C
00046 C     External:
00047 C     --------
00048 C     None
00049 C
00050 C     References:
00051 C     ----------
00052 C     O. Thual, Simple ocean-atmosphere interpolation.
00053 C               Part A: The method, EPICOA 0629 (1992)
00054 C               Part B: Software implementation, EPICOA 0630 (1992)
00055 C     See also OASIS manual (1995)
00056 C
00057 C     History:
00058 C     -------
00059 C       Version   Programmer     Date      Description
00060 C       -------   ----------     ----      -----------
00061 C       1.1       O. Thual       93/04/15  created
00062 C       2.0       L. Terray      95/10/01  modified: new structure
00063 C       2.3       L. Terray      99/09/15  changed periodicity variables
00064 C
00065 C %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
00066 C
00067 C* ---------------------------- Include files ---------------------------
00068 C
00069       USE mod_unit
00070 C
00071 C* ---------------------------- Argument declarations -------------------
00072 C
00073       REAL (kind=ip_realwp_p) px(kngx,kngy), py(kngx,kngy)
00074       CHARACTER*8 cdper
00075 C
00076 C* ---------------------------- Poema verses ----------------------------
00077 C
00078 C %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
00079 C
00080 C*    1. Left or right
00081 C        -------------
00082 C
00083 C* Periodic grid with kper overlapped points
00084 C
00085       IF (cdper .EQ. 'P') THEN
00086           IF (kx .EQ. 1) THEN
00087               pxi = 0.5 * (px(kx,ky) + px(kngx-kper,ky) - 360.)
00088               pxs = 0.5 * (px(kx,ky) + px(kx+1,ky))
00089              ELSE IF (kx .EQ. kngx) THEN
00090               pxi = 0.5 * (px(kx-1,ky) + px(kx,ky))
00091               pxs = 0.5 * (px(kx,ky) + px(1+kper,ky) + 360. )
00092             ELSE
00093               pxi = 0.5 * (px(kx-1,ky) + px(kx,ky))
00094               pxs = 0.5 * (px(kx,ky) + px(kx+1,ky))
00095           ENDIF
00096 C
00097 C* Regional grid
00098 C
00099         ELSE IF (cdper .EQ. 'R') THEN
00100           IF (kx .EQ. 1) THEN
00101               pxi = px(kx,ky)
00102               pxs = 0.5 * (px(kx,ky) + px(kx+1,ky))
00103             ELSE IF (kx .EQ. kngx) THEN
00104               pxi = 0.5 * (px(kx-1,ky) + px(kx,ky))
00105               pxs = px(kx,ky)
00106             ELSE
00107               pxi = 0.5 * (px(kx-1,ky) + px(kx,ky))
00108               pxs = 0.5 * (px(kx,ky) + px(kx+1,ky))
00109           ENDIF
00110       END IF
00111 C
00112 C
00113 C*    2. Bottom or top (idem for both types of grid)
00114 C        -------------------------------------------
00115 C True only if it is a global grid in latitude [-90 , 90]
00116 C or as it is the case for regional models if the first and last
00117 C latitude row are masked ---> then we only go through the else statement.
00118 C
00119       IF (ky .EQ. 1) THEN
00120           pyi = -90.
00121           pys = 0.5 * (py(kx,ky) + py(kx,ky+1))
00122         ELSE IF (ky .EQ. kngy) THEN
00123           pyi = 0.5 * (py(kx,ky-1) + py(kx,ky))
00124           pys = 90.
00125         ELSE
00126           pyi = 0.5 * (py(kx,ky-1) + py(kx,ky))
00127           pys = 0.5 * (py(kx,ky)+ py(kx,ky+1))
00128       ENDIF
00129 C
00130 C* End of routine
00131 C
00132       RETURN
00133       END
00134