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#
# Copyright 2001 Free Software Foundation, Inc.
#
# This file is part of GNU Radio
#
# 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 2, 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., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.
#
function plotfftavgk_db (all_data, k, sample_rate)
if (nargin == 2)
sample_rate = 1.0;
endif;
if ((m = nargchk (2,3,nargin)))
usage (m);
endif;
len = 1024;
## len = 8192;
##window = ones (len, 1);
#window = kaiser (len, 5);
window = hanning (len);
s = zeros (len,1);
count = min (100, floor (length (all_data)/len));
for i = 0:count-1;
data = all_data((k+i)*len + 1 : (k+i+1)*len);
s = s + abs (fft (data.*window));
endfor;
s = s ./ count;
incr = sample_rate/len;
if is_complex (all_data);
min_x = -sample_rate/2;
max_x = sample_rate/2 - incr;
x = min_x:incr:max_x;
y = 20 * log10(fftshift(s));
plot (x, y);
else
min_x = 0
max_x = sample_rate/2 - incr;
x = min_x:incr:max_x;
y = 20 * log10(s(1:len/2));
plot (x, y);
endif;
i = find (y == max(y))
x(i)
y(i)
endfunction
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