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4
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1 function retval = cond (a) |
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2 |
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3 # usage: cond (a) |
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4 # |
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5 # Return the condition number of a, computed using the singular values |
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6 # of a. |
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7 # |
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8 # See also: norm, svd |
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9 |
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10 if (nargin == 1) |
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11 [nr, nc] = size (a); |
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12 if (nr == 0 && nc == 0) |
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13 if (strcmp (propagate_empty_matrices, "false")) |
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14 error ("cond: empty matrix is invalid as argument"); |
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15 endif |
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16 if (strcmp (propagate_empty_matrices, "warn")) |
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17 printf ("warning: cond: argument is empty matrix\n"); |
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18 endif |
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19 retval = 0.0; |
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20 endif |
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21 sigma = svd (a); |
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22 retval = sigma (1) / sigma (length (sigma)); |
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23 else |
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24 error ("usage: cond (a)"); |
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25 endif |
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26 |
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27 endfunction |
