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annotate scripts/elfun/lcm.m @ 715:6544b83ef9e9

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[project @ 1994-09-20 18:40:02 by jwe] Initial revision
author jwe
date Tue, 20 Sep 1994 18:40:02 +0000
parents
children 3470f1e25a79
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6544b83ef9e9 [project @ 1994-09-20 18:40:02 by jwe]
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1 function l = lcm (a, ...)
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2
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3 # lcm (a) returns the least common multiple of the entries of the
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4 # integer vector a.
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5 # lcm (a1, ..., ak) is the same as lcm([a1, ..., ak]).
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6
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7 # Written by KH (Kurt.Hornik@ci.tuwien.ac.at) on Sep 16, 1994
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8 # Copyright Dept of Statistics and Probability Theory TU Wien
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9
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10 if (nargin > 1)
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11 va_start;
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12 for k=2:nargin;
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13 a = [a, va_arg()];
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14 endfor
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15 endif
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16
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17 if (round(a) != a)
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18 error("lcm: all arguments must be integer");
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19 endif
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20
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21 if (any(a) == 0)
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22 l = 0;
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23 else
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24 a = abs(a);
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25 l = a(1);
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26 for k=1:(length(a)-1)
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27 l = l * a(k+1) / gcd(l, a(k+1));
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28 endfor
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29 endif
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30
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31 endfunction
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32