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* Copyright 2004,2005 Free Software Foundation, Inc.
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* This file is part of GNU Radio
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* GNU Radio is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 3, or (at your option)
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* GNU Radio is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with GNU Radio; see the file COPYING. If not, write to
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* the Free Software Foundation, Inc., 51 Franklin Street,
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* Boston, MA 02110-1301, USA.
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#ifndef INCLUDED_GR_SINGLE_POLE_REC_FILTER_FF_H
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#define INCLUDED_GR_SINGLE_POLE_REC_FILTER_FF_H
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#include <gr_sync_block.h>
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#include <gr_single_zero_rec.h>
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class gr_single_zero_rec_filter_ff;
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typedef boost::shared_ptr<gr_single_zero_rec_filter_ff> gr_single_zero_rec_filter_ff_sptr;
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gr_single_zero_rec_filter_ff_sptr
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gr_make_single_zero_rec_filter_ff (double alpha, unsigned int vlen=1);
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* \brief single zero recursive filter with float input, float output
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* The input and output satisfy a difference equation of the form
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y[n] - (1-alpha) y[n-1] = -alpha x[n]
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* with the corresponding system function
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H(z) = {alpha - (1-alpha) z^{-1}}
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* Note that some texts define the system function with a + in the denominator.
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* If you're using that convention, you'll need to negate the feedback tap.
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class gr_single_zero_rec_filter_ff : public gr_sync_block
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friend gr_single_zero_rec_filter_ff_sptr
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gr_make_single_zero_rec_filter_ff (double alpha, unsigned int vlen);
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std::vector<gr_single_zero_rec<float,float,double> > d_rec;
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gr_single_zero_rec_filter_ff (double alpha, unsigned int vlen);
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~gr_single_zero_rec_filter_ff ();
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void set_taps (double alpha);
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int work (int noutput_items,
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gr_vector_const_void_star &input_items,
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gr_vector_void_star &output_items);