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annotate scripts/polynomial/polyreduce.m @ 1025:f558749713f1

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[project @ 1995-01-11 20:52:10 by jwe]
author jwe
date Wed, 11 Jan 1995 20:52:10 +0000
parents 3470f1e25a79
children bceff7ccdb79
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1 # Copyright (C) 1995 John W. Eaton
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2 #
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3 # This file is part of Octave.
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4 #
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5 # Octave is free software; you can redistribute it and/or modify it
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6 # under the terms of the GNU General Public License as published by the
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7 # Free Software Foundation; either version 2, or (at your option) any
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8 # later version.
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9 #
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10 # Octave is distributed in the hope that it will be useful, but WITHOUT
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11 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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12 # FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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13 # for more details.
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14 #
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15 # You should have received a copy of the GNU General Public License
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16 # along with Octave; see the file COPYING. If not, write to the Free
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17 # Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
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18
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19 function p = polyreduce (p)
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20
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21 # usage: polyreduce(c)
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22 #
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23 # Reduces a polynomial coefficient vector to a minimum number of terms,
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24 # i.e. it strips off any leading zeros.
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25 #
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26 # SEE ALSO: poly, roots, conv, deconv, residue, filter, polyval, polyvalm,
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27 # polyderiv, polyinteg
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28
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29 # Written by Tony Richardson (amr@mpl.ucsd.edu) June 1994.
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30
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31 index = find (p == 0);
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32
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33 index = find (index == 1:length(index));
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34
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35 if (length (index) == 0)
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36 return;
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37 endif
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38
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39 if(length(p)>1)
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40 p = p (index (length (index))+1:length(p));
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41 endif
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42
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43 if (length (p) == 0)
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44 p = 0;
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45 endif
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46
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47 endfunction