annotate scripts/elfun/lcm.m @ 3979:e0b7a493e5a8

[project @ 2002-07-10 17:45:34 by jwe]
author jwe
date Wed, 10 Jul 2002 17:45:34 +0000
parents d25bc039237b
children 2cbc6f37b0c2
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1 ## Copyright (C) 1996, 1997 John W. Eaton
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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 2, or (at your option)
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8 ## 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, write to the Free
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17 ## Software Foundation, 59 Temple Place - Suite 330, Boston, MA
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18 ## 02111-1307, USA.
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19
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20 ## -*- texinfo -*-
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21 ## @deftypefn {Mapping Function} {} lcm (@var{x}, @code{...})
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22 ## Compute the least common multiple of the elements elements of @var{x}, or
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23 ## the list of all the arguments. For example,
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24 ##
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25 ## @example
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26 ## lcm (a1, ..., ak)
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27 ## @end example
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28 ##
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29 ## @noindent
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30 ## is the same as
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31 ##
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32 ## @example
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33 ## lcm ([a1, ..., ak]).
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34 ## @end example
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35 ## @end deftypefn
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36 ## @seealso{gcd, min, max, ceil, and floor}
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37
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38 ## Author: KH <Kurt.Hornik@ci.tuwien.ac.at>
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39 ## Created: 16 September 1994
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40 ## Adapted-By: jwe
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41
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42 function l = lcm (a, varargin)
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44 if (nargin == 0)
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45 usage ("lcm (a, ...)");
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46 endif
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48 if (nargin > 1)
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49 k = 1;
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50 for i = 2:nargin
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51 a = [a, varargin{k++}];
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52 endfor
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53 endif
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54
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55 if (round (a) != a)
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56 error ("lcm: all arguments must be integer");
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57 endif
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59 if (any (a) == 0)
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60 l = 0;
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61 else
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62 a = abs (a);
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63 l = a (1);
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64 for k = 1:(length (a) - 1)
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65 l = l * a(k+1) / gcd (l, a(k+1));
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66 endfor
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67 endif
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68
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69 endfunction