The W3FB05 routine converts the coordinates of a location from
the grid(i,j) coordinate system overlaid on the polar
stereographic map projection true at 60 degrees N or S
latitude to the natural coordinate system of
latitude/longitude on the earth.
USAGE: CALL W3FB05 (XI, XJ, XMESHL, ORIENT, ALAT, ALONG)
XI I OF THE POINT RELATIVE TO THE NORTH OR S. POLE
XJ J OF THE POINT RELATIVE TO THE NORTH OR S. POLE
XMESHL MESH LENGTH OF GRID IN KM AT 60 DEGREES(<0 IF SH)
(190.5 LFM GRID, 381.0 NH PE GRID,-381.0 SH PE GRID)
ORIENT ORIENTATION WEST LONGITUDE OF THE GRID
(105.0 LFM GRID, 80.0 NH PE GRID, 260.0 SH PE GRID)
ALAT LATITUDE IN DEGREES (<0 IF SH)
ALONG WEST LONGITUDE IN DEGREES
All parameters in the calling statement must be
real. The range of allowable latitudes is from a pole to
30 degrees into the opposite hemisphere.
The grid used in this subroutine has its origin (i=0,j=0)
at the pole, so if the user's grid has its origin at a point
other than a pole, a translation is required to get i and j for
input into w3fb05. The subroutine grid is oriented so that
gridlines of i=constant are parallel to a west longitude
supplied by the user. The earth's radius is taken to be 6371.2 km.
This code will not vectorize, it is normaly used in a
double do loop with w3ft01, w3ft00, etc. to vectorize it,
put it in line, put w3ft01, w3ft00, etc. in line.
||Library contains Fortran 90 decoder/encoder
routines for GRIB edition 1. (Fortran90)
Date posted: 2/22/2007