;+
; @file_comments 
; 
; 
; @categories
; 
; 
; @param NUM 
;
;
; @param RECSTART
; 
;
; @returns
; 
; 
; @restrictions
; 
; 
; @examples
;
;
; @history
; 
;
; @version
; $Id$
;-
FUNCTION scan_grib_nbits, num, recstart
;
  compile_opt idl2, strictarrsubs
;

;
  nrec =  n_elements(recstart)
  nbits = bytarr(nrec)
;
  FOR i = 0L, nrec-1 DO BEGIN
    offset = recstart[i]+8
    a = assoc(num, bytarr(1, /nozero), offset-1)
    sizepds = bit2int([binary(a[1]), binary(a[2]), binary(a[3])])
    flag = binary(a[8])
    gdsnotomitted = flag[0]
    bmsnotomitted = flag[1]
    ddd =  bit2int([binary(a[27]), binary(a[28])], /checkneg)
;
    offset = offset+sizepds
;
    IF gdsnotomitted THEN BEGIN
      a = assoc(num, bytarr(1, /nozero), offset-1)
      sizedds = bit2int([binary(a[1]), binary(a[2]), binary(a[3])])
      offset = offset+sizedds
    ENDIF
;
    IF bmsnotomitted THEN BEGIN
      a = assoc(num, bytarr(1, /nozero), offset-1)
      sizebms = bit2int([binary(a[1]), binary(a[2]), binary(a[3])])
      offset = offset+sizebms
    ENDIF

    a = assoc(num, bytarr(1, /nozero), offset-1)
    nbits[i] = a[11]

  ENDFOR
;
  RETURN, nbits
END