pro setclrtab,clrtab,nlevels,ps=ps
;
loadct,clrtab
tvlct,r,g,b,/get
nc = !d.table_size
if (keyword_set(ps)) then begin ; white background, black foreground
  r(0) = 255
  g(0) = 255
  b(0) = 255
  r(nc-1) = 0
  g(nc-1) = 0
  b(nc-1) = 0
endif else begin ; black background, white foreground
  r(0) = 0
  g(0) = 0
  b(0) = 0
  r(nc-1) = 255
  g(nc-1) = 255
  b(nc-1) = 255
endelse
 tvlct,r,g,b
;tvlct,r[1:nc-1],g[1:nc-1],b[1:nc-1]
;tvlct,r,g,b,1
!p.color = nc-1
!p.background = 0
print,'setclrtab: nc=',nc,' !p.color=',!p.color,' !p.background=',$
  !p.background,' !d.table_size=',!d.table_size
end