function hdr_intf, attr, title, title2, units, minlat, maxlat, minlon, maxlon, $
                   misval, mskval, order, nl, nt, nv, verbose=verbose

; VARIABLE DESCRIPTIONS: 
;   nl   Number of levels
;   nt   Number of time dimensions
;   nv   Number of variables

size_out=size(attr)
if size_out(size_out(0)+1) ne 8 then begin
	if (keyword_set(verbose)) then print,'Header information not read'
	return,attr
endif else begin
        size_array=size(attr.a)
        if (size_array(0) GT 2) then begin
          if (attr.t_lnr.no_times EQ 1) then nt=1
          if (attr.z_lvl.no_levels EQ 1) then nl=1
          if (keyword_set(verbose)) then $
             print,'Extracting time ',nt,' level ',nl,' and var ',nv
          b=extract(attr,/whole,time=nt,level=nl,var=nv,verbose=verbose)
        endif else begin
          b=attr
        endelse
	if n_elements(title) eq 0 then title=b.ttl_str
	if n_elements(title2) eq 0 then begin
           title2=''
           if (strlen(b.t_ext) GT 0) then title2=title2 + $
              ' ' + strtrim(b.t_ext) + ', '
           title2=title2 + ' ' + strtrim(attr.var_strc(nv-1).subtitle)
;           if (strlen(b.z_ext) GT 0) then title2=title2 + $
;              ', level ' + strtrim(b.z_ext)
           endif
	if n_elements(units) eq 0 then units=attr.var_strc(nv-1).var_units
	if n_elements(minlat) eq 0 then $
           minlat=b.y_lnr.startpt - b.y_lnr.incr * 0.5
	if n_elements(maxlat) eq 0 then $
           maxlat=minlat + b.y_lnr.gridpts * b.y_lnr.incr
	if n_elements(minlon) eq 0 then $
           minlon=b.x_lnr.startpt - b.x_lnr.incr * 0.5
	if n_elements(maxlon) eq 0 then $
           maxlon=minlon + b.x_lnr.gridpts * b.x_lnr.incr
	if n_elements(misval) eq 0 then misval=b.unk
	if n_elements(mskval) eq 0 then mskval=b.msk_val
	if n_elements(order) eq 0 then order=b.order_info

        if (keyword_set(verbose)) then begin
	  print,'The title is ',title 
	  print,'The secondary title is ',title2
	  print,'Units ',units
	  print,'Starting Y-coordinate',minlat
	  print,'Ending Y-coordinate',maxlat
	  print,'Starting X-coordinate',minlon
	  print,'Ending X-coordinate',maxlon
	  print,'Undefined value',misval
	  print,'Mask value',mskval
	  print,'Order is ',order
        endif
        return,reform(b.a)
endelse
end