;****************************************************************************
; Author  :  Josh Grant, COAPS
;
; Description : This program takes a divergence file which is in the format
;               previously specified for this project and grids it based on
;               the month of the swath.  Each monthly value is then used to
;               calculate the monthly average of each month in the NSCAT
;               mission. 
;
; **Warning** : Due to poor planning on my part and lack of time the bulk of
;               this program is not commented like it should be.
;****************************************************************************

;@/usr/people/whalley/lidl/jday2date.pro
PRO WRITEMONTH, grid, totals, month, year, monthlyDirectory
  stringFormat = STRCOMPRESS( '(i' + STRING( 2 ) + '.' $
                 + STRING( 2 ) + ')', /REMOVE_ALL )
  file_name = monthlyDirectory + STRTRIM( year, 1 ) + $
    STRING( month + 1, format = stringFormat ) + ".monavg"
  FOR lon = 0, 359 DO BEGIN
    FOR lat = 0, 179 DO BEGIN
      IF ( totals( month, lon, lat ) NE 0 ) THEN BEGIN
        grid( month, lon, lat ) = grid( month, lon, lat ) / $
          totals( month, lon, lat )
      ENDIF
    ENDFOR
  ENDFOR
  OPENW, output, file_name, /GET_LUN
  FOR lat = 0, 179 DO BEGIN
    printf, output, FORMAT = '(360F10.3)', grid( month, *, lat )
  ENDFOR
  FREE_LUN, output
  print, "Finished " + file_name     

END

  base = "/Net/NSCAT/people/grant/diverg_proj/"
  swathsDirectory = base + "div2grid/data/daily_swath/"
  monthlyDirectory = base + "div2grid/data/gridded/monthly/"

  tempFile = "temp.div"

  miss = 99999.0
  time = LON64ARR( 18000 )
  data = FLTARR( 3, 48, 18000 )

  grid = FLTARR( 12, 360, 180 )
  totals = FLTARR( 12, 360, 180 )

  ny = 0
  nx = 0

  previousMonth = 9

  grid( *, *, * ) = miss
  totals( *, *, * ) = 0.0
  
  start = 336
  endday = 366
  FOR year = 1996, 1997 DO BEGIN
    IF ( year EQ 1997 ) THEN BEGIN
      start = 1
      endday = 180
    ENDIF
    FOR number = start, endday DO BEGIN
      stringFormat = STRCOMPRESS( '(i' + STRING( 3 ) + '.' $
                    + STRING( 3 ) + ')', /REMOVE_ALL )

      file_name = swathsDirectory + STRTRIM( year, 1 ) + $
        STRING( number, format = stringFormat ) + '.div.gz'

      READFILE, file_name, tempFile, data, time, ny, nx, error
      IF ( error EQ 0 ) THEN BEGIN
        check = 0
        min2date, time( 0 ), ptyear, ptmonth1, ptday, pthour, ptmin
        min2date, time( ny - 1 ), ptyear, ptmonth2, ptday, pthour, ptmin
        IF ( ptmonth1 NE ptmonth2 ) THEN check = 1 ELSE ptmonth = ptmonth1

        FOR col = 0, nx - 1 DO BEGIN
          FOR row = 0, ny - 1 DO BEGIN
            IF ( data( 2, col, row ) NE miss ) THEN BEGIN
              grid_lat = FIX( data( 0, col, row ) + 90.5 )
              grid_lon = FIX( data( 1, col, row ) + 0.5 )
              IF ( check EQ 1 ) THEN BEGIN
                min2date, time( row ), ptyear, ptmonth, ptday, pthour, ptmin
              ENDIF

              IF ( grid_lon GT 359 ) THEN grid_lon = 359
              IF ( grid_lat GT 179 ) THEN grid_lat = 179
              IF ( grid( ptmonth - 1, grid_lon, grid_lat ) EQ miss ) THEN BEGIN
                grid( ptmonth - 1, grid_lon, grid_lat ) = data( 2, col, row )
                totals( ptmonth - 1, grid_lon, grid_lat ) = 1.0
              ENDIF ELSE BEGIN
                grid( ptmonth - 1, grid_lon, grid_lat ) = $
                  grid( ptmonth - 1, grid_lon, grid_lat ) + data( 2, col, row )
                totals( ptmonth - 1, grid_lon, grid_lat ) = $
                  totals( ptmonth - 1, grid_lon, grid_lat ) + 1.0
              ENDELSE
            ENDIF
          ENDFOR
        ENDFOR

        print, "Finished " + file_name

      ENDIF
      IF ( number NE 259 AND number NE 180 ) THEN BEGIN
        JDAY2DATE, number, filemonth, fileday, year
        IF ( fileday EQ 3 ) THEN BEGIN
          ptyear = year
          IF ( filemonth EQ 1 ) THEN filemonth = 11 & ptyear = year - 1 $
            ELSE filemonth = filemonth - 2
          WRITEMONTH, grid, totals, filemonth, ptyear, monthlyDirectory
        ENDIF
      ENDIF
    ENDFOR
  ENDFOR

  WRITEMONTH, grid, totals, 5, 1997, monthlyDirectory

END