Hi all,
I am encountering this problem of converting latlon to ij coordinates using wrf_user_ll_to_ij function. When I convert max lat and long to ij coordinates, the function give me grid y_coordinates larger than total number of grid points in y_dimension. In the same way conversion of minimum longitude results in a negative number. However, the old latlon to ij conversion function "wrf_user_latlon_to_ij" does the conversion correctly.
I wrote the following small code to recheck this. I used both old and new functions to show the difference. There are 651 x 651 grid points in the wrfout file.
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/wrf/WRFUserARW.ncl"
begin
f1 = addfile("/wrfout_d01_2006-06-02_13:00:00.nc","r")
opts = True
xLat_f1 = wrf_user_getvar(f1,"XLAT", 0)
xLong_f1 = wrf_user_getvar(f1,"XLONG", 0)
xLat_min = min(xLat_f1)
xLat_max = max(xLat_f1)
xLong_min = min(xLong_f1)
xLong_max = max(xLong_f1)
; New ll_to_ij function
min_loc_ll = wrf_user_ll_to_ij(f1,xLong_min,xLat_min,opts)
max_loc_ll = wrf_user_ll_to_ij(f1,xLong_max,xLat_max,opts)
print("min. x-coord fm ll func.: "+min_loc_ll(0)+"; min. y_coord fm ll func.: "+min_loc_ll(1))
print("max. x-coord fm ll func.: "+max_loc_ll(0)+"; max. y_coord fm ll func.: "+max_loc_ll(1))
; Old latlon_to_ij function
min_loc_latlon = wrf_user_latlon_to_ij(f1,xLat_min,xLong_min)
max_loc_latlon = wrf_user_latlon_to_ij(f1,xLat_max,xLong_max)
print("min. x-coord fm latlon func.: "+min_loc_latlon(1)+"; min. y_coord fm latlon func.: "+min_loc_latlon(0))
print("max. x-coord fm latlon func.: "+max_loc_latlon(1)+"; max. y_coord fm latlon func.: "+max_loc_latlon(0))
end
;;;
Output from wrf_user_ll_to_ij
min. x-coord fm ll func.: -16; min. y_coord fm ll func.: 0
max. x-coord fm ll func.: 651; max. y_coord fm ll func.: 657
Output from wrf_user_latlon_to_ij
min. x-coord fm latlon func.: 0; min. y_coord fm latlon func.: 0
max. x-coord fm latlon func.: 650; max. y_coord fm latlon func.: 650
;----------------------------------------------------------
I am just wondering if there is some bug in this function (wrf_user_ll_to_ij).
Cheers,
---- Basit A. Khan, Ph.D. Postdoctoral Research Fellow Division of Physical Sciences & Engineering Office# 3204, Level 3, Building 1, King Abdullah University of Science & Technology 4700 King Abdullah Blvd, Box 2753, Thuwal 23955 –6900, Kingdom of Saudi Arabia. Office: +966(0)2 808 0276, Mobile: +966(0)5 0860 3617 E-mail: basitali.khan@kaust.edu.sa<mailto:basitali.khan@kaust.edu.sa> Skype name: basit.a.khan
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Received on Tue Jun 12 07:48:31 2012
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