20090126, 20:09  #1 
Apr 2007
Spessart/Germany
2·3^{4} Posts 
integrator failed
Hello,
today I try to factor a number using nfs (for the first time) in msieve. I choosed a number (C116), put it in the worktodo.ini and started 'msieve np'. After a few minutes of calculating I got an error as a screenoutput: Code:
integrator failed 1.073703e013 3.829712e018 error: size score computation failed Have I to pay attention about this error? And if the polynomial selection has finished, what I have to do to sieve this number with 2 cores of my computer? Atm I'm thinking of this procedure: 1) copy worktodo.ini, msieve.dat.p and msieve.fb to another directory with a second instance of msieve. 2) start worker1 with 'msieve ns 1,10000' and worker 2 with 'msieve ns 10001,20000' 3) merge 2 *.dat files and process 'msieve nc' for this datfile 4) if sieving still needed I restart with 2) and new lines '20001,30000' and '30001,40000'. This I will do until I get a result Any objections about this plan, maybe something is completely wrong. In the meantime I got the described error again (with other numbers after 'integrator failed'). hm ? best regards, Matthias 
20090126, 21:17  #2 
Tribal Bullet
Oct 2004
5·709 Posts 
The next version will greatly reduce (hopefully eliminate) the integrator problems that you see. The errors are not fatal, just annoying. As for the sieving, using msieve will be 5x slower than using GGNFS (for a C116 you'd be saving close to a week of runtime).

20090126, 22:24  #3 
Apr 2007
Spessart/Germany
2×3^{4} Posts 
ok, in the meantime I finished the poly selection with msieve and got a polynomial. As you suggested, I will ignore the 'integrator' errors.
Of course it sounds very interesting to use GGNFS, but I have no plan how to use it. I downloaded the win32bit Core2 version Jeff Gilchrist is offering at his page (thanks for it btw, I can not compile such binaries for myself. I only have a Pascalcompiler...). Can I use now the poly I got by msieve or should I run a new polyselection with the tools of GGNFS? Hm, this looks more complicate than using msieve. Is there something like a 'step by step introduction' how to use GGNFS to factor a number? best regards, Matthias 
20090126, 23:57  #4 
Tribal Bullet
Oct 2004
5·709 Posts 
The msieve polynomial is usable within GGNFS (you'll have to create a text file with the polynomial in it, that GGNFS can read). See this thread for the central clearinghouse of people comparing notes on running GGNFS. Yes, it's a lot more complex than just starting msieve, but there is no substitute for the tools that GGNFS contains.

20090127, 01:07  #5  
Jun 2003
Ottawa, Canada
3×17×23 Posts 
Quote:
As an example, when msieve finishes generating a polynomial, it creates an msieve.fb file which looks something like this: Code:
N 542199118360122645149018222712631403787793963895701957093138322222784637474878020968003860466806398192243491945916177216280574963 SKEW 168279.97 R0 6331679219837515495939907 R1 156433515642929 A0 71923817076071821269252524150400 A1 1552973346849705835047567360 A2 1842020125749195022561 A3 78887013322320122 A4 348969912 A5 53280 Code:
n: 542199118360122645149018222712631403787793963895701957093138322222784637474878020968003860466806398192243491945916177216280574963 Y0: 6331679219837515495939907 Y1: 156433515642929 c0: 71923817076071821269252524150400 c1: 1552973346849705835047567360 c2: 1842020125749195022561 c3: 78887013322320122 c4: 348969912 c5: 53280 skew: 168279.97 type: gnfs ./factMsieve.pl file.poly Last fiddled with by Jeff Gilchrist on 20090127 at 01:08 

20090128, 03:54  #6 
Apr 2007
Spessart/Germany
2·3^{4} Posts 
@ jason: thank you for you explanations, I already startet to read the thread. I hope to get some answers there.
@ Jeff: of course thank you, too. I very appreciate these first steps. I will give cygwin a try and use the same directorystructure you have postet in the other thread. But it sounds complicate, I will need some time to figure out how it works. I'm sure I will come back with some (stupid) questions . best regards, Matthias 
Thread Tools  
Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
GMPECM 7.0dev assertion failed!  Antonio  GMPECM  9  20150310 08:21 
Can an OS config be OK after RAM failed?  RickC  Hardware  8  20101028 03:31 
Assertion failed  Andi47  GMPECM  2  20090804 14:11 
connection failed  musos  Information & Answers  1  20081212 14:29 
Test 1: failed?  No0dles  Hardware  12  20051105 09:23 