;+
;
; @file_comments
; Initfile for Netcdf file. define all the grid parameters through
; an appropriate call to <pro>computegrid</pro>
;
; @categories
; Grid
;
; @param ncfilein {in}{required}{type=scalar string}
; A string giving the name of the NetCdf file
;
; @keyword START1 {default=0}{type=scalar: 0 or 1}
; Index the axis from 1 instead of 0 when using
; /xyindex and/or /zindex
;
; @keyword ZAXISNAME {default='z', 'level', 'lev', 'depth...'}{type=scalar string}
; A string giving the name of the variable in the file
; that contains the [xyz]axis.
;
; @keyword XYINDEX {default=0}{type=scalar: 0 or 1}
; To define the x/y axis with index instead of using
; the values contained in X/YAXISNAME.
; x/yaxis = keyword_set(start1) + findgen(jpi/jpj)
; this forces key_onearth = 0
;
; @keyword ZINDEX {default=0}{type=scalar: 0 or 1}
; To define the z axis with index instead of using
; the values contained in ZAXISNAME.
; zaxis = keyword_set(start1) + findgen(jpk)
;
; @keyword _EXTRA
; Used to pass keywords to <pro>computegrid</pro>, 
; <pro>ncdf_getaxis</pro>, <pro>ncdf_getmask</pro> and <pro>isafile</pro>
;
; @uses
; common.pro
;
; @restrictions
; Change the grid parameters (see <pro>computegrid</pro>)
;
; @restrictions
; the file must contain an x and an y axis. (1 ou 2 dimensional array)
;
; @examples
; IDL> initncdf,'toto.nc',glam=[-180,180]
;
; @history
; Sebastien Masson (smasson\@lodyc.jussieu.fr)
;                      8 May 2002
;
; @version
; $Id$
;
;-
PRO initncdf, ncfilein $
              , ZAXISNAME=zaxisname, START1=start1 $
              , XYINDEX=xyindex, ZINDEX=zindex $
              , _EXTRA=ex
;
  compile_opt idl2, strictarrsubs
;
@common
;----------------------------------------------------------
; check the name of the file
  ncfile = isafile(FILENAME = ncfilein, IODIRECTORY = iodir, _extra = ex)
  if size(ncfile, /type) NE 7 then BEGIN
    ras = report( 'initncdf cancelled')
    return
  endif
; if the file is stored on tape
  if !version.os_family EQ 'unix' then spawn, 'file '+ncfile+' > /dev/null'
;----------------------------------------------------------
; open the file
  cdfid = ncdf_open(ncfile)
; what is inside the file
  inside = ncdf_inquire(cdfid)
;----------------------------------------------------------
; name of the variables
  namevar = strarr(inside.nvars)
  for varid = 0, inside.nvars-1 do begin
    invar = ncdf_varinq(cdfid, varid)
    namevar[varid] = strlowcase(invar.name)
  ENDFOR
;----------------------------------------------------------
; find the x/yaxis
 ncdf_getaxis, cdfid, dimidx, dimidy, xaxis, yaxis $
               , START1 = start1, XYINDEX = xyindex, ROMSGRID = romsgrid, _extra = ex
;----------------------------------------------------------
; find the zaxis
  IF keyword_set(romsgrid) THEN BEGIN
    FOR i = 0, inside.ndims-1 DO BEGIN
      ncdf_diminq, cdfid, i, name, size
      CASE strlowcase(name) OF
        's_rho':zaxis = reverse(indgen(size))
        's_u':zaxis = reverse(indgen(size))
        's_v':zaxis = reverse(indgen(size))
        's_psi':zaxis = reverse(indgen(size))
        's_w':zaxis = reverse(indgen(size-1))
        ELSE:
      ENDCASE
    ENDFOR
    IF (where(namevar EQ 'h'))[0] NE -1 THEN BEGIN
      ncdf_varget, cdfid, 'h', romsh
    ENDIF ELSE romsh = -1
  ENDIF ELSE BEGIN
    if keyword_set(zaxisname) then zaxisname = strlowcase(zaxisname) ELSE zaxisname = 'z'
    zvarid = (where(namevar EQ 'nav_lev' or namevar EQ zaxisname OR namevar EQ 'level' OR namevar EQ 'lev' OR strmid(namevar, 0, 5) EQ 'depth'))[0]
    if zvarid EQ -1 AND inside.ndims GT 3 then begin
      ras = report( 'initncdf: the zaxis was not found..., check the use of ZAXISNAME keyword if you want to find one...')
;     stop
    endif
; read the zaxis
    if zvarid NE -1 THEN ncdf_varget, cdfid, zvarid, zaxis
  ENDELSE
  IF keyword_set(zindex) AND keyword_set(zaxis) THEN $
     zaxis = keyword_set(start1) + findgen(n_elements(zaxis))
;----------------------------------------------------------
; mask
  tmask = ncdf_getmask(cdfid, _extra = ex)
;----------------------------------------------------------
;
  ncdf_close, cdfid
;
;----------------------------------------------------------
; call compute the grid
  if NOT keyword_set(zaxis) then BEGIN
    computegrid, xaxis = xaxis, yaxis = yaxis $
                 , mask = tmask, onearth = 1b - keyword_set(xyindex), ROMSH = romsh, _EXTRA = ex
  ENDIF ELSE BEGIN
    computegrid, xaxis = xaxis, yaxis = yaxis, zaxis = zaxis $
                 , mask = tmask, onearth = 1b - keyword_set(xyindex), ROMSH = romsh, _EXTRA = ex
  ENDELSE
  IF n_elements(time) EQ 0 THEN time = 0
  jpt = n_elements(time)
;----------------------------------------------------------

  return
end