/usr/share/octave/packages/communications-1.1.1/bsc.m is in octave-communications-common 1.1.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 | ## Copyright (C) 2007 Sylvain Pelissier <sylvain.pelissier@gmail.com>
##
## 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 3 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.
##
## You should have received a copy of the GNU General Public License along with
## this program; if not, see <http://www.gnu.org/licenses/>.
## -*- texinfo -*-
## @deftypefn {Function File} {@var{y} =} bsc (@var{data}, @var{p})
## Send @var{data} into a binary symetric channel with probability
## @var{p} of error one each symbol.
## @end deftypefn
function [ndata] = bsc(data,p)
if (nargin < 1); usage('ndata = bsc(data,p)'); end
if(isscalar(p) ~= 1 || p > 1 || p < 0)
error('p muste be a positive scalar less than one');
exit;
end
if(any(data(:) ~= floor(data(:))) || any(data(:) > 1) || any(data(:) < 0))
error('data must be a binary sequence');
exit;
end
ndata = data;
ndata(find(data == 0)) = randsrc(size(ndata(find(data == 0)),1),size(ndata(find(data == 0)),2),[-1 -2;1-p p]);
ndata(find(data == 1)) = randsrc(size(ndata(find(data == 1)),1),size(ndata(find(data == 1)),2),[1 0;1-p p]);
ndata(find(ndata == -1)) = 0;
ndata(find(ndata == -2)) = 1;
|