Ticket #1407 (closed enhancement: fixed)

Opened 6 years ago

Last modified 6 years ago

[with patch, with positive review] deciding that generators don't generate an order in some extensions can be way way too slow.

Reported by: was Owned by: was
Priority: major Milestone: sage-2.9
Component: number theory Keywords:
Cc: Work issues:
Report Upstream: Reviewers:
Authors: Merged in:
Dependencies: Stopgaps:

Description

Consider this: 

sage: P.<a,b,c> = QQ[2^(1/2), 2^(1/3), 2^(1/5)]
sage: P.order([1,a])
*should* go boom very quickly... but runs forever and runs out of RAM

In the situation above, a satisfies only a quadratic polynomial so there is no possible way it will generate an order in a degree 8 field, since the index [O_K : ZZ[a]] is clearly infinite. Sage should quickly detect this and give an error message, but doesn't for some reason.

Attachments

trac1407.patch Download (15.9 KB) - added by was 6 years ago.
trac_1407-2.patch Download (1.9 KB) - added by craigcitro 6 years ago.

Change History

Changed 6 years ago by was

comment:1 Changed 6 years ago by was

  • Summary changed from deciding that generators don't generate an order in some extensions can be way way too slow. to [with patch] deciding that generators don't generate an order in some extensions can be way way too slow.

Changed 6 years ago by craigcitro

comment:2 Changed 6 years ago by craigcitro

  • Summary changed from [with patch] deciding that generators don't generate an order in some extensions can be way way too slow. to [with patch, with positive review] deciding that generators don't generate an order in some extensions can be way way too slow.

Minor doctest touchups.

comment:3 Changed 6 years ago by mabshoff

  • Status changed from new to closed
  • Resolution set to fixed

Merged in 2.9.rc0.

Note: See TracTickets for help on using tickets.