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annotate scripts/signal/bartlett.m @ 3499:3e3e14ad5149

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[project @ 2000-01-31 05:18:07 by jwe]
author jwe
date Mon, 31 Jan 2000 05:18:13 +0000
parents e031284eea27
children 38c61cbf086c
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1 ## Copyright (C) 1995, 1996, 1997 Andreas Weingessel
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2 ##
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3 ## This program is free software; you can redistribute it and/or modify
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4 ## it under the terms of the GNU General Public License as published by
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5 ## the Free Software Foundation; either version 2, or (at your option)
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6 ## any later version.
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7 ##
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8 ## This program is distributed in the hope that it will be useful, but
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9 ## WITHOUT ANY WARRANTY; without even the implied warranty of
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10 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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11 ## General Public License for more details.
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12 ##
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13 ## You should have received a copy of the GNU General Public License
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14 ## along with this file. If not, write to the Free Software Foundation,
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15 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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16
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17 ## -*- texinfo -*-
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18 ## @deftypefn {Function File} {} bartlett (@var{m})
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19 ## Return the filter coefficients of a Bartlett (triangular) window of
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20 ## length @var{m}.
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21 ##
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22 ## For a definition of the Bartlett window, see e.g. A. V. Oppenheim &
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23 ## R. W. Schafer, "Discrete-Time Signal Processing".
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24 ## @end deftypefn
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25
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26 ## Author: AW <Andreas.Weingessel@ci.tuwien.ac.at>
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27 ## Description: Coefficients of the Bartlett (triangular) window
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28
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29 function c = bartlett (m)
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30
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31 if (nargin != 1)
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32 usage ("bartlett (m)");
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33 endif
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34
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35 if (! (is_scalar (m) && (m == round (m)) && (m > 0)))
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36 error ("bartlett: m has to be an integer > 0");
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37 endif
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38
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39 if (m == 1)
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40 c = 1;
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41 else
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42 m = m - 1;
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43 n = fix (m / 2);
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44 c (1 : n+1) = 2 * (0 : n)' / m;
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45 c (n+2 : m+1) = 2 - 2 * (n+1 : m)'/m;
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46 endif
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47
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48 c = c';
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49
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50 endfunction