;------------------------------------------------------------
;------------------------------------------------------------
;------------------------------------------------------------
;+
;
; @file_comments
; Allows to choose the type of the label we want to use at the time of a contour.
;
; @categories
; Graphics
;
; @param CAS {in}{required}
; Number of the type of the label we want to trace
;	
; @param MIN {in}{required}
; Smallest value for the drawing of the contour.
;
; @param MAX {in}{required}
; Biggest value for the drawing of the contour.
;
; @keyword INTERVALLE {default=20}
; Value of an interval between two isolines. By default, it is calculated to
; draw 20 isolines. In all cases, this keyword must be returned have a nice
; caption. If levels do not contain regular intervals, put it at -1.
;
; @keyword NLEVEL {default=20}
; Number of contour to be drawn. Active if LABEL=0 or is not specified.
;
; @param NCONTOUR {out}
; Number of contour to be drawn.
;
; @param LEVEL_Z2D {out}
; Vector containing values of contours we draw.
;
; @param COLNUMB {out}
; Vector containing the number of colors which will serve to fill contours.
;
; @uses
; common.pro
;
; @history
; Sebastien Masson (smasson\@lodyc.jussieu.fr)
;			7/5/98
;
; @version
; $Id$
;
;-
;------------------------------------------------------------
;------------------------------------------------------------
;------------------------------------------------------------
pro label, cas, min, max, ncontour, level_z2d, colnumb, NLEVEL = nlevel $
          ,INTERVALLE=intervalle, STRICTFILL = strictfill
;
  compile_opt idl2, strictarrsubs
;
@common
   if !d.name EQ 'PS' OR !d.name EQ 'Z' then BEGIN
      old_dname = !d.name
      thisOS = !VERSION.OS_FAMILY
      thisOS = STRMID(thisOS, 0, 3)
      thisOS = STRUPCASE(thisOS)
      CASE thisOS of
         'MAC': SET_PLOT, thisOS
         'WIN': SET_PLOT, thisOS
         ELSE: SET_PLOT, 'X'
      ENDCASE
      !p.BACKGROUND=(!d.n_colors-1) < 255
      !p.color=0
      if !d.n_colors gt 256 then !p.background='ffffff'x
      ncoul = !D.n_Colors < 256
      set_plot,old_dname
   ENDIF ELSE ncoul = !D.n_Colors < 256
   case cas of
      0: begin
; nlevel label between the min and the max
         if keyword_set(Nlevel) eq 0 then ncontour=20 else ncontour=nlevel
         ncontour = 1 > ncontour
         level_z2d  = min + (max-min)*(findgen(Ncontour)/Ncontour)
         colnumb    = ncoul*(findgen(Ncontour))/Ncontour+ncoul/(2*ncontour)
         intervalle = level_z2d[1]-level_z2d[0]
      end
      1: begin
; a certain number of label from the min to the nearest possible to the
; max with a constant step by interval
         ncontour  = fix((max-min)/intervalle)
         ncontour = 1 > ncontour
         level_z2d = min + intervalle*findgen(Ncontour)
         colnumb   = ncoul*(findgen(Ncontour))/Ncontour+ncoul/(2*ncontour)
         max=level_z2d[Ncontour-1]+intervalle
      end
; label to do same sss than dessier

      2: begin
         lct, 63, file = 'palette.tbl'
         level_z2d  = [20, 25, 30, 31, 32, 33, 33.5, 34+.25*findgen(16)]
         ncontour=23
         colnumb    = findgen(23)+1
         masx = 37.75
         intervalle = -1
         return
      end
      3: begin
; Readinf of intervals + palette in the file GMT

         label_gmt, min, max, intervalle, ncoul, ncontour, level_z2d, colnumb

      end
      else: begin
         ras = report('Le numero de label demande n''existe pas')
      end
   ENDCASE
   if keyword_set(strictfill) then begin
      ncontour = ncontour+1
      level_z2d = [level_z2d, max]
      colnumb = [colnumb, ncoul-1]
   endif
   return
end