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Sisyphus wrote:
<blockquote cite="mid03e601c7070c$f3cb56e0$0100a8c0@desktop" type="cite">
<pre wrap="">----- Original Message -----
From: "Luis Alexandre" <a class="moz-txt-link-rfc2396E" href="mailto:lm.alexandre@gmail.com"><lm.alexandre@gmail.com></a>
To: <a class="moz-txt-link-rfc2396E" href="mailto:gmp-discuss@swox.com"><gmp-discuss@swox.com></a>
Sent: Monday, November 13, 2006 1:31 AM
Subject: mpz_invert function
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<pre wrap="">Hello everybody, I'm in despaired stiuation: I'm programming a DSA
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<pre wrap=""><!---->algorithm
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<pre wrap="">in C with GMP and I need to calculate the inverse of an mpz_t without
modulo. I've tried the mpz_invert function, but this function as three
parameters and the third one is the mod (modulo).
Is there a way of using this function with an infinite modulo, or there is
any other way.
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<pre wrap=""><!---->
Sorry ... maybe it's just me, but I struggle to comprehend what the inverse
of a number, modulo infinity, would be ... and why the DSA algorithm would
need it.
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<br>
Hello,<br>
it is not possible to calculate an inverse of n without modulo in N
because there can be no number x so that n*x yields 1 (what is the
definition of the inverse); the inverse in N is defined *only* for
residue classes. The DSA Algorithm uses the inverse with modulo.<br>
<br>
Best regards<br>
<br>
Michael Plugge<br>
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