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annotate scripts/general/is_symmetric.m @ 73:f3c9042fd609

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[project @ 1993-08-30 14:49:08 by jwe]
author jwe
date Mon, 30 Aug 1993 14:54:55 +0000
parents 2d10ab3ee69d
children 16a24e76d6e0
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1 function retval = is_symmetric (x,tol)
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3 # Usage: is_symmetric (x {,tol})
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4 #
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5 # If x is symmetric, return the dimension of x, otherwise, return 0.
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6 #
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7 # See also: size, rows, columns, length, is_matrix, is_scalar,
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8 # is_square, is_vector
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9
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10 # Written by A. S. Hodel (scotte@eng.auburn.edu) August 1993.
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11
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2d10ab3ee69d [project @ 1993-08-13 20:09:16 by jwe]
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12 if (nargin == 1 || nargin == 2)
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13 if ((retval = is_square (x)))
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14 if (nargin == 1)
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15 tol = eps;
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16 endif
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17 if (norm (x - x') / norm(x) > tol)
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18 retval = 0;
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19 endif
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20 endif
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21 else
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22 error ("usage: is_symmetric (x {,tol})");
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23 endif
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24
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25 endfunction