Hi, On Sunday, June 20, 2021 at 10:18:50 AM UTC+9 zsc...@gmail.com wrote:
> I have reason to believe that the point P is not torsion and so Magma is > correct and Sage is incorrect. I don't know enough about the algorithms > used to work with points on hyperelliptic Jacobians and so I'm not > confident in my ability to track down what's going on. > By my own computation, I confirm that Sage is incorrect. Looking at the Sage source code, I see that Sage uses Cantor's reduction algorithm based on Mumford representation of divisors by ideals. Sage wrongly computes 5*P to (1) unit ideal. So I guess there seems a bug in the implementation of Cantor's algorithm... -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-support/041e7893-9ff3-45cd-9535-39e9bea54ee8n%40googlegroups.com.
