NAME:angle.pro (fom angle.F,v 2.2 in OPA8.2)
PURPOSE:Compute angles between grid lines and direction of the North
CALLING SEQUENCE:
angle, fileocemesh, gcosu, gsinu, gcosv, gsinv, gcost, gsint
INPUTS:
fileocemesh a netcdf file that contains (at least):
glamu, gphiu: longitudes and latitudes at U-points
glamv, gphiv: longitudes and latitudes at V-points
glamf, gphif: longitudes and latitudes at F-points
KEYWORD PARAMETERS:
IODIRECTORY: the directory path where is located fileocemesh
/DOUBLE: use double precision (default is float)
OUTPUTS:
gsinu,gcosu : sinus and cosinus of the angle
gsinv,gcosv between north-south direction
gsint,gcost and the j-direction of the mesh
RESTRICTIONS: to compute the lateral boundary conditions, we assume
that:
(1) the first line is similar to the second line
=> gcosu[*, 0] = gcosu[*, 1]
=> gsinu[*, 0] = gsinu[*, 1]
(2) the grid follows OPA x periodicity rule, first column is
equal to the next to last column
=> gcosv[0, *] = gcosv[jpj-2, *]
=> gsinv[0, *] = gsinv[jpj-2, *]
MODIFICATION HISTORY:
--------------
Original : 96-07 (O. Marti)
98-06 (G. Madec)
Feb 2005: IDL adaptation S. Masson