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annotate scripts/special-matrix/hilb.m @ 4:b4df021f796c

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[project @ 1993-08-08 01:26:08 by jwe] Initial revision
author jwe
date Sun, 08 Aug 1993 01:26:08 +0000
parents
children 16a24e76d6e0
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b4df021f796c [project @ 1993-08-08 01:26:08 by jwe]
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1 function retval = hilb (n)
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2
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3 # usage: hilb (n)
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4 #
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5 # Return the Hilbert matrix of order n. The i, j element of a Hilbert
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6 # matrix is defined as
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7 #
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8 # H (i, j) = 1 / (i + j - 1);
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9 #
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10 # See also: hankel, vander, hadamard, invhilb, toeplitz
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12
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13 if (nargin != 1)
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14 error ("usage: hilb (n)");
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15 endif
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16
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17 nmax = length (n);
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18 if (nmax == 1)
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19 retval = zeros (n);
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20 for j = 1:n
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21 for i = 1:n
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22 retval (i, j) = 1 / (i + j - 1);
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23 endfor
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24 endfor
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25 else
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26 error ("hilb: expecting scalar argument, found something else");
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27 endif
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28
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29 endfunction