PRO sub_var3, im, jm, km, fName, num2, num3, ivar, var, ii, jj, kk

;; Script to read a 3-D variable from hycom archive file

;;----------------------------------------------------------------------

;; Input:

;; fName : file name '.a'

;; im, jm, km : dimension for full domain

;; num2/3 : number of 2d/3d variables -- .b

;; ivar : index of the 3d variable (starting from 1st num3)

;; [ii jj kk] : dimension for sub domain [optional]

;;----------------------------------------------------------------------

;;

;; A. Bozec Feb, 2014

compile_opt idl2, strictarrsubs

; im = 320 & jm = 384

; km = 41

; fName = '/Users/abozec/IDL/IDL_DATA/POP1v6/expt_36.9/RAW_adjusted/369_archm.0003_m01.a'

; num2 = 29

; num3 = 7

; ivar = 6

close,/all

;; Dimensions of the domain

idm = im

jdm = jm

ijdm = idm*jdm

kdm = km

;; NPAD size

npad = ceil(float(idm)*jdm/4096)*4096

; print, n_elements(ii)

IF (n_elements(ii) NE 0.) THEN BEGIN

ni = n_elements(ii)

nj = n_elements(jj)

nk = n_elements(kk)

var = dblarr(ni, nj, nk)

FOR k = 0, nk-1 DO BEGIN

offs = (num2+num3*kk[k]+ivar-1.D)

for j = 0, nj-1 do begin

dstart = (offs*npad + jj[j]*idm + ii[0])*4.

dstart = long64(dstart)

result = read_binary(fName, data_start = dstart, data_type = 4, data_dims = [ni], endian = 'big')

var[*, j, k] = result[*]

endfor

endfor

;; Put nan on missing values

var[where(var GT 1e20)] = !values.f_nan

ENDIF ELSE BEGIN

;; Tab Declaration

var = dblarr(idm, jdm, kdm)

FOR k = 0, kdm-1 DO BEGIN

dstart = (num2+num3*k+ivar-1.D)*npad*4.D

dstart = long64(dstart)

result = read_binary(fName, data_start = dstart, data_type = 4, data_dims = [ijdm], endian = 'big')

FOR j = 0, jdm-1 DO BEGIN

FOR i = 0, idm-1 DO var[i, j, k] = result[j*idm+i]

ENDFOR

ENDFOR

;; Put nan on missing values

var[where(var GT 1e20)] = !values.f_nan

ENDELSE

END