On 30 October 2016 at 13:16, Vincent Delecroix <[email protected]> wrote: > Dear all, > > (cross post sage-devel, sage-nt) > > While working on something else I discovered that it is possible to > multiply vectors over QQ by elements of Zmod rings > {{{ > sage: Zmod(5).an_element() * (QQ^2).an_element() > (0, 0) > sage: parent(_) > Vector space of dimension 2 over Ring of integers modulo 5 > }}} > However it is not possible to multiply rationals by elements of Zmod ring > {{{ > sage: Zmod(5).an_element() * QQ.an_element() > Traceback (most recent call last): > ... > TypeError: unsupported operand parent(s) for '*': 'Ring of integers > modulo 5' and 'Rational Field' > }}} > > I think that the behavior of these operations should be similar. Do > you think that > A) the above is fine (with explanation please) > B) we should raise an error in the first example > C) the second example should work and the answer be an element of Zmod(5) > D) ? >
I vote C (so that QQ works the same as QQ^1) with the usual proviso that if the denominator is not coprime to the modulus, an error is raised. > Cheers > Vincent > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "sage-nt" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send an email to [email protected]. Visit this group at https://groups.google.com/group/sage-nt. For more options, visit https://groups.google.com/d/optout.
