/* -*- c++ -*- */
/*
 * Copyright 2008,2010,2012 Free Software Foundation, Inc.
 *
 * GNU Radio 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 3, or (at your option)
 * any later version.
 *
 * GNU Radio 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "probe_density_b_impl.h"
#include <gr_io_signature.h>
#include <iostream>

namespace gr {
  namespace digital {

    probe_density_b::sptr
    probe_density_b::make(double alpha)
    {
      return gnuradio::get_initial_sptr
	(new probe_density_b_impl(alpha));
    }

    probe_density_b_impl::probe_density_b_impl(double alpha)
      : gr_sync_block("density_b",
		      gr_make_io_signature(1, 1, sizeof(char)),
		      gr_make_io_signature(0, 0, 0))
    {
      set_alpha(alpha);
      d_density = 1.0;
    }

    probe_density_b_impl::~probe_density_b_impl()
    {
    }

    void
    probe_density_b_impl::set_alpha(double alpha)
    {
      d_alpha = alpha;
      d_beta = 1.0-d_alpha;
    }

    int
    probe_density_b_impl::work(int noutput_items,
			       gr_vector_const_void_star &input_items,
			       gr_vector_void_star &output_items)
    {
      const char *in = (const char *)input_items[0];

      for(int i = 0; i < noutput_items; i++)
	d_density = d_alpha*(double)in[i] + d_beta*d_density;

      return noutput_items;
    }

  } /* namespace digital */
} /* namespace gr */