Karim Belabas on Wed, 11 Jul 2012 16:34:16 +0200


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Re: Hello 

* Ahmad Kamal [2012-07-11 11:34]:
> Hi , i want to ask please about the command      x=random(p)    :
> 
> what if i want to be sure that x has an inverse Mod p .

randominv(N) =
{ my(r);
  until(gcd(r,N) == 1, r = random(N));
  r
}

? vector(10,i,randominv(30))
%1 = [17, 1, 11, 17, 11, 29, 29, 17, 11, 7]

    K.B.
-- 
Karim Belabas, IMB (UMR 5251)  Tel: (+33) (0)5 40 00 26 17
Universite Bordeaux 1          Fax: (+33) (0)5 40 00 69 50
351, cours de la Liberation    http://www.math.u-bordeaux1.fr/~belabas/
F-33405 Talence (France)       http://pari.math.u-bordeaux1.fr/  [PARI/GP]
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