## Copyright (C) 1998-2003 Joao Cardoso.
##
## This program is free software; you can redistribute it and/or modify it
## under the terms of the GNU General Public License as published by the
## Free Software Foundation; either version 2 of the License, or (at your
## option) any later version.
##
## This program is distributed in the hope that it will be useful, but
## WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
## General Public License for more details.
##
## This file is part of plplot_octave.

## n = free_fig
##
## return the number of an unused plot figure

function n = free_fig

  global __pl

  if (!exist("__pl") || !struct_contains (__pl,"inited"))
    n = 0;
    return;
  endif

  if (any(__pl.open == 0))
    n = min(find(__pl.open == 0))-1;
  else
    n = length(__pl.open);
  endif

endfunction


