Re: need for a hash function

[Phil Carmody <thefatphil@yahoo.co.uk>]

--- Igor Schein <igor@txc.com> wrote:
> Hi,
> 
> Here's a scenario.  I need to to check whether or not 2 polynomials
> are isomorphic.  The polynomials are big, so the usual methods like
> nfisisom() and friends are computationally costly.  But, I am able to
> compute relatively cheaply my own invariant and compare it for both
> polynomials.  However, the value of the function which computes
> the invariant takes on huge vectors.

Is it possible to just calculate the invariant modulo small primes?
If they're huge vectors of small values, then that won't be a gain.

Phil


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