;----------------------------------------------------- 
; program to read a 15 minute CAVE SAM file and return 
;   the data portion and number of extra variables 
; 
; Example Input 
; 
;   filein = 'arm_C01_200101_avg.v3.0' 
; 
;----------------------------------------------------- 

pro readsam,filein, $         ; Input 
            data,next         ; Output 

; define file name 

  fn = filein 

  b64  = bytarr(64) 
  b32  = bytarr(32) 
  b04  = bytarr(4) 
  year = bytarr(4) 
  mon  = bytarr(4) 
  pdng = bytarr(10216)                 ;<-*******
  lat  = 1.0 
  lon  = 1.0 
  elev  = 1.0 
  rext  = 1.0 
  labl = strarr(50) 
  openr,1,fn ; ,/swap_if_little_endian 

; read and parse header 

     readu,1,b64 
     name=string(b64) 
     readu,1,b04 
     year=string(b04) 
     readu,1,b04 
     mon =string(b04) 
     readu,1,lat 
     readu,1,lon 
     readu,1,elev 
     readu,1,rext 
     next = Fix(rext) 
     print,name 
     print,year,mon,lat,lon,elev,next 
     n1 = 21+next                      ;<-*******
     for i=0,n1 do begin 
       readu,1,b32 
       labl(i) = string(b32) 
       print,labl(i) 
     endfor
     for i=n1+1,49 do begin            ;<-*******
       readu,1,b32                     ;<-*******
     endfor                            ;<-*******
     readu,1,pdng                      ;<-*******
                            
; read data 

     din = fltarr(2976) 
     data = fltarr(2976,22+next)     
     for i=0,21+next do begin 
       readu,1,din 
       data(0:2975,i) = din(0:2975) 
     endfor 
  close,1 

  openw,5,'lwup.dat'  
  for i=0,30 do begin 
    i1 = i*96         ;   LW Up
    i2 = i1+95        ;  /
    printf,5,data(i1:i2,3),format='(10f8.2)'
  endfor 
  close,5 

end
;--------------------
;  Header Definitions
;--------------------
;    Sequence
;    Character (Len=64) :: Site_ID 		    !   64 bytes    64 
;    Character (Len=4)  :: year			    !    4 bytes    68
;    Character (Len=4)  :: mon			    !    4 bytes    72
;    Real    :: lat				    !    4 bytes    76
;    Real    :: lon				    !    4 bytes    80
;    Real    :: elev				    !    4 bytes    84
;    Real    :: extras				    !    4 bytes    88
;    Character (Len=32), Dimension(50) :: label     ! 1600 bytes  1688
;    Character (Len=10216) :: padding		    !10216 bytes 11904
;--------------------
; rec #   
;  0     - Header
;  1     - Cos(Sol Zen Ang)   (-----) (yes)
;  2     - LW Flux DN         (W/m*m) (yes)
;  3     - LW Flux UP         (W/m*m) (yes)
;  4     - SW Global DN       (W/m*m) (yes)
;  5     - SW Global UP       (W/m*m) (yes)
;  6     - SW Direct Normal   (W/m*m) (yes)
;  7     - SW Dif DN UnAdj    (W/m*m) (yes)
;  8     - Total SW Dn,Dir+Dif(W/m*m) (yes)
;  9     - Temp Surface Air   (Deg C) (yes)
; 10     - Sfc Pressure       (   mb) (yes)
; 11     - Sfc Wind Speed     (  m/s) (yes)
; 12     - Sfc Wind Dir       (+degN) (yes)
; 13     - Sfc Rel Humidity   (    %) (yes)
; 14     - Cloud Fract (SWFA) (  0-1) (yes)
; 15     - Aer OD-1 nnnn nm   (-----) ( no)
; 16     - Aer OD-2 nnnn nm   (-----) ( no)
; 17     - Aer OD-3 nnnn nm   (-----) ( no)
; 18     - Aer OD-4 nnnn nm   (-----) ( no)
; 19     - Aer OD-5 nnnn nm   (-----) ( no)
; 20     - Aer OD-6 nnnn nm   (-----) ( no)
; 21     - Aer OD-7 nnnn nm   (-----) ( no)