Waldek Hebisch <[email protected]> writes:
> Martin Rubey wrote:
>> Do we really want to declare all integers less than 2 non-prime? Eg.,
>> prime?(-5) gives false.
>>
>> Martin
>>
>> (Apart from this, I was a little surprised that we don't even have
>> prime? for polynomials, etc.)
>
> In UniqueFactorizationDomain we have:
>
> prime?: % -> Boolean
> ++ prime?(x) tests if x can never be written as the product of two
> ++ non-units of the ring,
> ++ i.e., x is an irreducible element.
>
>
> So the problem is that apropriate polynomial domains should have
> UniqueFactorizationDomain.
OK, I see there is a default definition. I guess this goes to the
discussion whether PolynomialFactorizationExplicit is a bad idea...
> And for consistency integers should use the same definition, that
> is apply absolute value before proper primality test.
Yes. Should I apply the following patch?:
prime? n ==
n < 0 => n := -n
n < two => false
Martin
--
You received this message because you are subscribed to the Google Groups
"FriCAS - computer algebra system" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/fricas-devel?hl=en.
