Hello, In the latest version of sage 6.4.1 the following code failed. > I didn't have any problem with 6.2 version of sage. > > [...] > > Sage failed to compute the canonical height. > any ideas? >
This computation is actually done by PARI; this was upgraded between versions 6.2 and 6.4.1. The problem seems to lie in PARI: gp > U = [-245369975623514803521420211420402474815373720177518420696215292670924086780233779586506792145074717/4069861969699146045958032034788970995470603578576, -696053034387689435413673877713244121475782562610666903528251447608130654196417305610237634015759861/4069861969699146045958032034788970995470603578576, -49356694805693369953216822105035107974083562942605713355717183776373331122267882948881129025418396548321363993080002121985116427859996985649385099335/4069861969699146045958032034788970995470603578576, 5996724761485351384753083917633373954904218466995628499407992841502416127074022935350022919212488198205525833829916828282709837728834438536000230267/1017465492424786511489508008697242748867650894644, -1943033527672518505867347410801184866534773028979571976479290969993491996577167508758887358085512124817167326269402804641328588524702957475568608101932310746684310251168033629279636817525659690186705/4069861969699146045958032034788970995470603578576]; gp > E = ellinit(U); gp > P = [283188771261789732541662405743402980051199109235, 39175522019721182331498476245534716069785193060995]; gp > ellisoncurve(E, P) %4 = 1 ? ellheight(E, P) *** at top-level: ellheight(E,P) *** ^-------------- *** at top-level: ellheight(E,P) *** ^-------------- *** ellheight: unknown type 64. The same with minimal models: gp > F = ellminimalmodel(E, &urst); gp > Q = ellchangepoint(P, urst); gp > ellheight(F, Q) *** at top-level: ellheight(F,Q) *** ^-------------- *** at top-level: ellheight(F,Q) *** ^-------------- *** ellheight: unknown type 64. Strangely, the error is slightly different (unknown type 0 instead of 64). Peter -- 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 post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.