annotate scripts/special-matrix/hilb.m @ 1315:611d403c7f3d

[project @ 1995-06-25 19:56:32 by jwe]
author jwe
date Sun, 25 Jun 1995 19:56:32 +0000
parents 3f257ab07921
children 5d29638dd524
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1 # Copyright (C) 1993, 1994, 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
16a24e76d6e0 [project @ 1993-12-03 02:00:15 by jwe]
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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, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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18
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19 function retval = hilb (n)
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20
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21 # usage: hilb (n)
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22 #
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23 # Return the Hilbert matrix of order n. The i, j element of a Hilbert
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24 # matrix is defined as
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25 #
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26 # H (i, j) = 1 / (i + j - 1);
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27 #
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28 # See also: hankel, vander, hadamard, invhilb, toeplitz
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31 if (nargin != 1)
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32 usage ("hilb (n)");
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33 endif
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34
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35 nmax = length (n);
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36 if (nmax == 1)
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37 retval = zeros (n);
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38 tmp = 1:n;
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39 for i = 1:n
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40 retval (i, :) = 1.0 ./ (tmp + (i - 1));
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41 endfor
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42 else
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43 error ("hilb: expecting scalar argument, found something else");
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44 endif
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45
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46 endfunction