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Fix warnings
author LYH <lyh.kernel@gmail.com>
date Fri, 27 Sep 2013 17:43:27 +0800
parents f3d52523cde1
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
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72c96de7a403 maint: update copyright notices for 2012
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1 ## Copyright (C) 2000-2012 Paul Kienzle
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2 ##
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3 ## This file is part of Octave.
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4 ##
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5 ## Octave is free software; you can redistribute it and/or modify it
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6 ## under the terms of the GNU General Public License as published by
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7 ## the Free Software Foundation; either version 3 of the License, or (at
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8 ## your option) any later version.
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9 ##
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10 ## Octave is distributed in the hope that it will be useful, but
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11 ## WITHOUT ANY WARRANTY; without even the implied warranty of
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12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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13 ## General Public License for more details.
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14 ##
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15 ## You should have received a copy of the GNU General Public License
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16 ## along with Octave; see the file COPYING. If not, see
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17 ## <http://www.gnu.org/licenses/>.
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19 ## -*- texinfo -*-
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20 ## @deftypefn {Function File} {} factorial (@var{n})
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21 ## Return the factorial of @var{n} where @var{n} is a positive integer. If
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22 ## @var{n} is a scalar, this is equivalent to @code{prod (1:@var{n})}. For
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23 ## vector or matrix arguments, return the factorial of each element in the
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24 ## array. For non-integers see the generalized factorial function
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25 ## @code{gamma}.
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26 ## @seealso{prod, gamma}
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27 ## @end deftypefn
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29 function x = factorial (n)
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30 if (nargin != 1)
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31 print_usage ();
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32 elseif (any (n(:) < 0 | n(:) != fix (n(:))))
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33 error ("factorial: N must all be non-negative integers");
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34 endif
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35 x = round (gamma (n+1));
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36 endfunction
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39 %!assert (factorial (5), prod (1:5))
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40 %!assert (factorial ([1,2;3,4]), [1,2;6,24])
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41 %!assert (factorial (70), exp (sum (log (1:70))), -128*eps)
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43 %!fail ("factorial (5.5)", "must all be non-negative integers")
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44 %!fail ("factorial (-3)", "must all be non-negative integers")
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