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annotate scripts/general/is_symmetric.m @ 59:2d10ab3ee69d

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[project @ 1993-08-13 20:09:16 by jwe] Initial revision
author jwe
date Fri, 13 Aug 1993 20:09:16 +0000
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children f3c9042fd609
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1 function retval = is_symmetric (x,tol)
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2
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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 if (nargin == 1 || nargin == 2)
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11 if ((retval = is_square (x)))
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12 if (nargin == 1)
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13 tol = eps;
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14 endif
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15 if (norm (x - x') / norm(x) > tol)
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16 retval = 0;
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17 endif
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18 endif
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19 else
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20 error ("usage: is_symmetric (x {,tol})");
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21 endif
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22
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23 endfunction