annotate scripts/special-matrix/hilb.m @ 2303:5cffc4b8de57

[project @ 1996-06-24 09:15:24 by jwe]
author jwe
date Mon, 24 Jun 1996 09:15:24 +0000
parents 5d29638dd524
children 2b5788792cad
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1 ### Copyright (C) 1996 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
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7 ### the Free Software Foundation; either version 2, or (at your option)
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8 ### any later version.
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9 ###
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10 ### Octave is distributed in the hope that it will be useful, but
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11 ### WITHOUT ANY WARRANTY; without even the implied warranty of
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12 ### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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13 ### General Public License 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, 59 Temple Place - Suite 330, Boston, MA
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18 ### 02111-1307, USA.
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19
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20 function retval = hilb (n)
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21
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22 ## usage: hilb (n)
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23 ##
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24 ## Return the Hilbert matrix of order n. The i, j element of a Hilbert
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25 ## matrix is defined as
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26 ##
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27 ## H (i, j) = 1 / (i + j - 1);
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28 ##
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29 ## See also: hankel, vander, hadamard, invhilb, toeplitz
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31
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32 if (nargin != 1)
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33 usage ("hilb (n)");
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34 endif
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35
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36 nmax = length (n);
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37 if (nmax == 1)
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38 retval = zeros (n);
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39 tmp = 1:n;
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40 for i = 1:n
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41 retval (i, :) = 1.0 ./ (tmp + (i - 1));
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42 endfor
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43 else
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44 error ("hilb: expecting scalar argument, found something else");
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45 endif
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46
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47 endfunction