function dbxval,entry,idltype,nvalues,sbyte,nbytes
;+
; NAME:	
;	DBXVAL
;
; PURPOSE:	
;	Quickly return a value of the specified item number	
; EXPLANATION:
;	Procedure to quickly return a value of the specified item number
;	from the entry.
;
; CALLING SEQUENCE:	
;	result = dbxval( entry, idltype, nvalues, sbyte, nbytes )
;
; INPUTS	
;	entry - entry or entries from data base (bytarr) 
;	idltype - idl data type (obtained with db_item_info)
;	nvalues - number of values to return (obtained with db_item)
;	sbyte - starting byte in the entry (obtained with db_item)
;	nbytes - number of bytes (needed only for string type)
;			(obtained with db_item)
;
; OUTPUTS:	
;	function value is value of the specified item in entry
;
; RESTRICTIONS:	
;	To increase speed the routine assumes that entry and item are
;	valid and that the data base is already opened using dbopen.
;
; REVISION HISTORY:	
;	version 0  D. Lindler Nov. 1987  (for new db format)
; 	Version 1, William Thompson, GSFC, 28 March 1994.
;			Incorporated into CDS library.
;	Version 2, Richard Schwartz, GSFC/SDAC, 23 August 1996
;			Allowed Entry to have 2 dimensions
; 	Version 2.1, 22 Feb 1997, JK Feggans, 
;				avoid reform for strings arrays.
;	Version 2.2 	Use overwrite with REFORM(),  W. Landsman,  May 1997
;	Converted to IDL V5.0   W. Landsman   September 1997
;-
;----------------------------------------------------------------
;
;
nentry = n_elements(entry[0,*])

case idltype of 		;case of data type
  1: val = byte(entry[sbyte:sbyte+nvalues-1,*],0,nvalues,nentry)
  2: val = fix(entry[sbyte:sbyte+nvalues*2-1,*],0,nvalues,nentry)
  3: val = long(entry[sbyte:sbyte+nvalues*4-1,*],0,nvalues,nentry)
  4: val = float(entry[sbyte:sbyte+nvalues*4-1,*],0,nvalues,nentry)
  5: val = double(entry[sbyte:sbyte+nvalues*8-1,*],0,nvalues,nentry)
  7: val = string( entry[sbyte:sbyte+nbytes-1,*])
endcase
;

if ( nvalues EQ 1 and nentry EQ 1) then return,val[0] else $
	if idltype eq 7 then return,val else return,reform(val,/overwrite)
end