[sage-support] sage ecm-interface
sorry to answer late to this thread. > Paul -- does GMP-ECM have a by-design hard limit of 4095 digits? the answer is no, this problem is likely related to pexpect. >> The real longterm solution to this problem is to totally rewrite the... > Thanks to Robert Miller that is already in Sage: yes instead of the pexpect interface one should use now ecmfactor. I am myself using it continuously and it is quite robust (unlike the pexpect interface which runs out of ttys after a few minutes). > Is there any reason we're still shipping the old interface? > How can I obtain the old functionality? I see no reason. However indeed the new interface performs only one curve. It is easy to extend to run several curves until a factor is found: # n is composite, returns a prime factor of n def Ecmfactor (n): b1 = 100 while True: p = ecmfactor (n, b1)[1] if is_pseudoprime(p): return p b1 = b1 + isqrt(b1) Paul Zimmermann --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] sage ecm-interface
Hallo, I'm wondering what goes wrong with tis: (sage 3.2 compiled from sources, ubuntu 8.04, quad core 2.4 GHz) sage: for k in range(14,21): : f=2^2^k+1;w=ecm.find_factor(f);[w[0],prod(w)==f] : [2, False] [523923, False] [1901173, False] [2, False] [2, False] [30539, False] [2, False] Are the exponents to big? Andrzej Chrzeszczyk --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
