view scripts/elfun/lcm.m @ 2311:2b5788792cad

[project @ 1996-07-11 20:18:38 by jwe]
author jwe
date Thu, 11 Jul 1996 20:18:38 +0000
parents 5cffc4b8de57
children 204cc7db6f4a
line wrap: on
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### Copyright (C) 1996 John W. Eaton
###
### This file is part of Octave.
###
### Octave is free software; you can redistribute it and/or modify it
### under the terms of the GNU General Public License as published by
### the Free Software Foundation; either version 2, or (at your option)
### any later version.
###
### Octave is distributed in the hope that it will be useful, but
### WITHOUT ANY WARRANTY; without even the implied warranty of
### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
### General Public License for more details.
###
### You should have received a copy of the GNU General Public License
### along with Octave; see the file COPYING.  If not, write to the Free
### Software Foundation, 59 Temple Place - Suite 330, Boston, MA
### 02111-1307, USA.

## usage: lcm (a, ...)
##
## lcm (a) returns the least common multiple of the entries of the
## integer vector a.
## lcm (a1, ..., ak) is the same as lcm([a1, ..., ak]).

function l = lcm (a, ...)

## Written by KH (Kurt.Hornik@ci.tuwien.ac.at) on Sep 16, 1994.

  if (nargin > 1)
    va_start;
    for k = 2:nargin;
      a = [a, (va_arg ())];
    endfor
  endif
  
  if (round (a) != a)
    error ("lcm:  all arguments must be integer");
  endif
  
  if (any (a) == 0)
    l = 0;
  else
    a = abs (a);
    l = a (1);
    for k = 1:(length (a) - 1)
      l = l * a(k+1) / gcd (l, a(k+1));
    endfor
  endif
    
endfunction