I did some testing and 1) ecm uses different seeds all the time, for example
echo 179424673 | /home/vbraun/Code/sage/local/bin/ecm -I 1 -c 1000000000 -cofdec -one 8.0 produces a different output every time. 2) Occasionally, ecm.py does a lot more factorizations and then eventually times out. Using strace, I see that, for example, the following is run when it eventually times out; echo 251951573867253012259144010843 | /home/vbraun/Code/sage/local/bin/ecm -I 1 -c 1000000000 -cofdec -one 8.0 Note that the command is rather slow (requires hundreds of trial steps) and that this prime (251951573867253012259144010843) is usually not used as an ecm input. So occasionally (but unlikely) one of the previous computations must yield this number as candidate and then factoring it takes a really long time. On Thursday, November 21, 2013 12:25:36 AM UTC-5, Volker Braun wrote: > Another random test failure that I get is from ecm, for example on eno or > mark: > > sage -t --long src/sage/interfaces/ecm.py > Timed out > ********************************************************************** > Tests run before process (pid=8764) timed out: > sage: f = ECM() ## line 169 ## > sage: n = 508021860739623467191080372196682785441177798407961 ## line 170 > ## > sage: f.one_curve(n, B1=10000, sigma=11) ## line 171 ## > [1, 508021860739623467191080372196682785441177798407961] > sage: f.one_curve(n, B1=10000, sigma=1022170541) ## line 173 ## > [79792266297612017, 6366805760909027985741435139224233] > sage: n = 432132887883903108009802143314445113500016816977037257 ## line > 175 ## > sage: f.one_curve(n, B1=500000, algorithm="P-1") ## line 176 ## > [67872792749091946529, 6366805760909027985741435139224233] > sage: n = 2088352670731726262548647919416588631875815083 ## line 178 ## > sage: f.one_curve(n, B1=2000, algorithm="P+1", x0=5) ## line 179 ## > [328006342451, 6366805760909027985741435139224233] > sage: sig_on_count() ## line 181 ## > 0 > sage: f = ECM() ## line 241 ## > sage: n = 508021860739623467191080372196682785441177798407961 ## line 242 > ## > sage: f.find_factor(n) ## line 243 ## > [79792266297612017, 6366805760909027985741435139224233] > sage: f=2^2^14+1 ## line 247 ## > sage: ecm.find_factor(f) ## line 248 ## > sage: sig_on_count() ## line 252 ## > 0 > sage: ecm.factor(602400691612422154516282778947806249229526581) ## line > 333 ## > [45949729863572179, 13109994191499930367061460439] > sage: ecm.factor((2^197 + 1)/3) # takes a long time ## line 336 > ## > > ********************************************************************** > > Has anybody seen this before or an idea what it is about? Random seed > integers that are sometimes bad, perhaps? > > And yes, this is with SAGE_TIMEOUT_LONG=5000 on mark. > -- You received this message because you are subscribed to the Google Groups "sage-devel" 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-devel. For more options, visit https://groups.google.com/groups/opt_out.
