;+
;
; .. _cronin_gustiness_ncdf.pro:
;
; =========================
; cronin_gustiness_ncdf.pro
; =========================
;
; Cronin gustiness correction on corrected sst on OAFLUX grid
;
; :file:`${PROJECT_OD}/TropFlux_sst_19890101_20091231.nc` have been produced by
; :ref:`sst_correction_ncdf.pro`.
;
; Cronin gustiness corrected ++ on corrected sst on OAFLUX grid
; is written in
; :file:`${PROJECT_OD}/TropFlux_gustiness_19890101_20091231.nc`
; if this file not already exists.
;
; This file will be used by :ref:`TropFlux_swr_BLND_19890101_20091231.pro` and
; :ref:`TropFlux_19890101_20091231.pro`.
;
;     .. graphviz::
;
;        digraph cronin_gustiness_ncdf {
;           graph [
;           rankdir="LR",
;           ]
;
;           file_in [shape=ellipse,fontname=Courier,label="${PROJECT_OD}/TropFlux_sst_19890101_20091231.nc"];
;           file_out [shape=ellipse,fontname=Courier,label="${PROJECT_OD}/TropFlux_gustiness_19890101_20091231.nc"];
;
;           cronin_gustiness_ncdf [shape=box,
;           fontname=Courier,
;           color=blue,
;           URL="http://forge.ipsl.jussieu.fr/tropflux/browser/trunk/src/cronin_gustiness_ncdf.pro",
;           label="${PROJECT}/src/cronin_gustiness_ncdf.pro"];
;
;           {file_in} -> {cronin_gustiness_ncdf} -> {file_out}
;        }
;
; EXAMPLES
; ========
;
; ::
;
;  IDL> cronin_gustiness_ncdf
;
; SEE ALSO
; ========
;
; :ref:`project_profile.sh`
;
; :ref:`mooring_corrections`
;
; :ref:`sst_correction_ncdf.pro`.
;
; :func:`initncdf <saxo:initncdf>`
; :func:`julday <saxo:julday>`
; :func:`ncdf_quickwrite <saxo:ncdf_quickwrite>`
;
; TODO
; ====
;
; coding rules
;
; why writing more than 1 timestep ?
;
; KNOWN ISSUES
; ============
;
; test of existence of fullfilename_in not very efficient because
; MUST_EXIST keyword of :func:`isafile <saxo:isafile>` not yet implemented
;
; EVOLUTIONS
; ==========
;
; - fplod 20110808T144208Z aedon.locean-ipsl.upmc.fr (Darwin)
;
;   * usage of ${PROJECT_OD}
;   * complete description
;   * remove v50 in output filename
;   * remove return statement
;
; - fplod 20101215T092619Z aedon.locean-ipsl.upmc.fr (Darwin)
;
;   * add graph in header
;
; - fplod 20101214T093615Z aedon.locean-ipsl.upmc.fr (Darwin)
;
;   * minimal header
;
; - pbk 2008
;
;   * creation
;
;-
pro cronin_gustiness_ncdf
;
@cm_4cal
@cm_4data
@cm_4mesh
@cm_4data
@cm_project
;
; test if ${PROJECT_OD} defined
CASE project_od_env OF
  '' : BEGIN
         msg = 'eee : ${PROJECT_OD} is not defined'
         ras = report(msg)
       STOP
       END
  ELSE: BEGIN
          msg = 'iii : ${PROJECT_OD} is ' + project_od_env
          ras = report(msg)
        END
 ENDCASE
;
; check if output data will be possible
iodirout = isadirectory(project_od_env)
;
; existence and protection for reading
IF (FILE_TEST(iodirout, /DIRECTORY, /EXECUTABLE, /READ) EQ 0) THEN BEGIN
   msg = 'eee : the directory' + iodirout  + ' is not accessible.'
   ras = report(msg)
   STOP
ENDIF
;
; existence and protection for writing
IF (FILE_TEST(iodirout, /DIRECTORY, /WRITE) EQ 0) THEN BEGIN
    msg = 'eee : the directory' + iodirout  + ' was not found.'
    ras = report(msg)
    STOP
ENDIF
;
da1=19880101 & da2=20101231
date1=19890101 & date2=20081231
;
; build data filename
filename='TropFlux_sst_19890101_20091231.nc'
;
; check if this file exists
fullfilename = isafile(iodirout + filename, NEW=0, /MUST_EXIST)
IF fullfilename[0] EQ '' THEN BEGIN
   msg = 'eee : the file ' + fullfilename + ' was not found.'
   ras = report(msg)
   STOP
ENDIF
;
; build output filename
filename_out = 'TropFlux_gustiness_19890101_20091231.nc'
fullfilename_out = iodirout + filename_out
; in order to avoid unexpected overwritten
IF (FILE_TEST(fullfilename_out) EQ 1) THEN BEGIN
   msg = 'eee : the file ' + fullfilename_out  + ' already exists.'
   ras = report(msg)
   STOP
ENDIF
;
initncdf, fullfilename
sst=read_ncdf('sst',da1,da2,file=fullfilename,/nostr) & sst=reform(sst-273.15)
help, sst

sst_clim=grossemoyenne(sst, 't',/nan)
;wg=0.175*sst_clim-3.17  ;; line fit obtained from the scatter (Cronin gustiness Vs ERAI SST)
;help, wg

jpt=n_elements(time)

wg_tot=sst*0.
for jt=0, jpt-1 do begin
    wg_tot(*,*,jt)=(((sst_clim(*,*)-23.7)*2.1/(29.8-23.7)) > 1.) <2.1
endfor
help, wg_tot

;; writing field
time=timegen(7670, units='days', start=julday(1,1,1989,0)) & jpt=n_elements(time)

cda0=string(jul2date(time(0)),format='(i8.8)')
cda1=string(jul2date(time(jpt-1)),format='(i8.8)')
tt=time-julday(1,1,1950,00,00,00)
xlon=reform(glamt(*,0) ) & ylat=reform(gphit(0,*))

ncfile='!' + fullfilename_out
lon_attr={units:'degrees_east',long_name:'Longitude'}
lat_attr={units:'degrees_north',long_name:'Latitude'}
time_attr={units:'days since 1950-01-01 00:00:00',long_name:'Time axis',time_origin:' 1950-JAN-01 00:00:00'}
gust_attr={units:'m/s',missing_value:valmask,long_name:'Climatological gustiness',short_name:'wg',axis:'TYX'}
globattr={source:'Climatological wind gustiness obtained by fitting cronins gustiness values against sst ',timerange:cda0+' - '+cda1}

ncfields = 'wg[longitude,latitude,time]=wg_tot:gust_attr; ' $
                      + 'longitude[]=xlon:lon_attr; ' $
                      + 'latitude[]=ylat:lat_attr; ' $
                      + 'tt[*time]=tt:time_attr ' $
                      + ' @ globattr'

@ncdf_quickwrite

end