That's definitely a bug since (2^63)*P is instantaneous as one would expect from 63 doublings.
I thought that I knew the actual code for group operations on elliptic curves, but when I do P.__mul__?? and see that it ends with return coercion_model.bin_op(left, right, mul) then I rather lose heart -- there is some clever magic here (the file sage/schemes/elliptic_curves/ell_point.py implements addition and negation but not multiplcation which is handled by some very general thing somewhere). Just not quite clever enough. As a stopgap, of course -((2^63)*P) works fine. John On 23 February 2015 at 16:27, William Stein <[email protected]> wrote: > Hi, > > A user reports (and I confirm) that if P is pretty much any point on > an elliptic curve over a finite field, then > > (-2^63)*P > > hangs forever. For example, > > E = EllipticCurve(GF(5),[0,1]) > P = E.random_element() > (-2^63)*P # hangs > > -- > William (http://wstein.org) > > -- > 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 [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/sage-support. > 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 http://groups.google.com/group/sage-nt. For more options, visit https://groups.google.com/d/optout.
