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annotate scripts/special-matrix/vander.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 = vander (c)
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2
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3 # usage: vander (c)
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4 #
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5 # Return the Vandermonde matrix whose next to last column is c.
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6 #
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7 # See also: hankel, hadamard, hilb, invhilb, toeplitz
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8
b4df021f796c [project @ 1993-08-08 01:26:08 by jwe]
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9 if (nargin != 1)
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10 error ("usage: vander (c)");
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11 endif
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12
b4df021f796c [project @ 1993-08-08 01:26:08 by jwe]
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13 nr = rows (c);
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14 nc = columns (c);
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15 if (nr == 1 && nc == 1)
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16 retval = 1;
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17 elseif (nr == 1 || nc == 1)
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18 n = length (c);
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19 if (n > 0)
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20 retval = zeros (n, n);
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21 for i = 1:n
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22 tmp = c(i);
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23 for j = 1:n
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24 retval (i, j) = tmp ^ (n - j);
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25 endfor
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26 endfor
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27 endif
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28 else
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29 error ("vander: argument must be a vector");
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30 endif
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31
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32 endfunction