Hello !
>> I don't know Is it very costly to compute ? The Moebius function
>> should be quick, shouldn't it ? O_o
>
> It is basically just self.lequal_matrix().inverse().change_ring(ZZ).
Oh. No Poset-specific algorithm. I see. Then we should earn a lot by doing so.
> More general question:
More general stuff at the end of mail.
On Thu, 11 Dec 2014, Nathann Cohen wrote:
More difficult is to optimize product() or ordinal_sum() etc.
And impossible, I think, is to optimize mobius_function_matrix, because one
can not know if it has already been calculated or not. Or maybe with
test w
