Okay, how about this:

[code]yafu "snfs((1145924053^19-1), (1145924053^19-1)/1145924052)"


02/09/15 14:52:16 v1.34.5 @ Gravemind, System/Build Info:
Using GMP-ECM 7.0-dev, Powered by GMP 6.0.0
detected Intel(R) Core(TM) i7-2600K CPU @ 3.40GHz
detected L1 = 32768 bytes, L2 = 8388608 bytes, CL = 64 bytes
measured cpu frequency ~= 3392.315710
using 1 random witnesses for Rabin-Miller PRP checks

===============================================================
======= Welcome to YAFU (Yet Another Factoring Utility) =======
======= bbuhrow@gmail.com =======
======= Type help at any time, or quit to quit =======
===============================================================
cached 78498 primes. pmax = 999983


>> nfs: checking for job file - job file found, testing for matching input
nfs: number in job file does not match input
nfs: checking for poly file - poly file found, testing for matching input
nfs: commencing nfs on c173: 13303345562369071347373642357283962165690034810857362376976557581034979264760880857329979228416336163023620060322595160533950610953053117227718347146617048626151678420617516
nfs: searching for brent special forms...
nfs: input divides 1145924053^19 - 1
gen: ========================================================
gen: considering the following polynomials:
gen: ========================================================

n: 11609273353806061265370527677242577124727315533174062723117149111933448853694957488622447753995075550629615426138725605991513485531633746725579983852731846338933183
# 1145924053^19-1, difficulty: 181.18, anorm: 7.84e+23, rnorm: 1.46e+50
# size = 1.798e-19, alpha = -0.220, combined = 1.576e-11, rroots = 2
type: snfs
size: 181
skew: 183.9878
c4: 1
c0: -1145924053
Y1: -1
Y0: 1975964677859978611243759163447028913685415493
m: 1975964677859978611243759163447028913685415493
n: 11609273353806061265370527677242577124727315533174062723117149111933448853694957488622447753995075550629615426138725605991513485531633746725579983852731846338933183
# 1145924053^19-1, difficulty: 199.30, anorm: -2.69e+35, rnorm: 4.30e+45
# size = 2.774e-21, alpha = -0.220, combined = 3.146e-12, rroots = 2
type: snfs
size: 199
skew: 0.0000
c4: 1504760928599007071085696877
c0: -1
Y1: -1
Y0: 1724341742096217794674180875621282481
m: 1724341742096217794674180875621282481
n: 11609273353806061265370527677242577124727315533174062723117149111933448853694957488622447753995075550629615426138725605991513485531633746725579983852731846338933183
# 1145924053^19-1, difficulty: 181.18, anorm: 4.99e+29, rnorm: 2.14e+41
# size = 3.134e-13, alpha = -1.041, combined = 4.390e-11, rroots = 1
type: snfs
size: 181
skew: 64.8382
c5: 1
c0: -1145924053
Y1: -1
Y0: 1724341742096217794674180875621282481
m: 1724341742096217794674180875621282481
n: 11609273353806061265370527677242577124727315533174062723117149111933448853694957488622447753995075550629615426138725605991513485531633746725579983852731846338933183
# 1145924053^19-1, difficulty: 208.36, anorm: -2.38e+46, rnorm: 6.33e+36
# size = 2.995e-16, alpha = -1.041, combined = 6.251e-13, rroots = 1
type: snfs
size: 208
skew: 0.0000
c5: 1724341742096217794674180875621282481
c0: -1
Y1: -1
Y0: 1504760928599007071085696877
m: 1504760928599007071085696877
[/code]

The last polynomial, though pretty clearly inferior, goes through to test sieving anyways, where what I assume is lasieve complains "Please set a skewness". Is it a Yafu bug that the polynomial has skew 0?

Edit: I'm in need of some more remedial education. It's obvious to everyone that I'm very rusty in these things. However, once upon a time when I understood things better, I had previously written some code do automatically generate OPN polys for me (not coincidentally, this is just before the time when I started trying to make YAFU friendlier to SNFS). I just played with that code:

[code]>>> my.opnpoly(1, 1145924053, 19, -1)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: opnpoly() missing 1 required positional argument: 'deg'
>>> my.opnpoly(1, 1145924053, 19, -1, 5)
Warning: this poly has a significantly larger difficulty than the number in question, consider doing some test sieving
c5: 1
c0: -1145924053
m: 1724341742096217794674180875621282481
skew: 64.8382324510266
type: snfs
size: 182
>>> my.opnpoly(1, 1145924053, 19, -1, 6)
I recommend the following polynomial:
c6: 1145924053
c0: -1
m: 1504760928599007071085696877
skew: 0.03091296727246838
type: snfs
size: 173[/code]
Is there a reason YAFU didn't consider the degree 6? Is that simply too high a degree for such a small number? I'm going to try test sieving right now, to see what happens.

Edit2: Yes, test sieving indicates the sextic is 20-30% slower (not terribly much, all things considered). Guess the number's too small.

Also, the -nt option (code that I wrote) is horribly broken. Lovely.

With that enormous leading coefficient the skew will be tiny. It appears yafu is printing using %0.4f instead of %0.4e, so I suppose any skew less than 0.0001 will be printed as 0. As you note, ideally it wouldn't be test sieving this at all.

[EDIT]:
Yes, some degrees are ignored based on input size. Unless, of course, the input has an algebraic factor.

First time I've seen yafu restart a factorization (twice) :-

[CODE]
02/21/15 09:57:01 v1.34.5 @ MESHGT, System/Build Info:
Using GMP-ECM 6.3, Powered by GMP 5.1.1
detected Intel(R) Core(TM) i5-3570K CPU @ 3.40GHz
detected L1 = 32768 bytes, L2 = 6291456 bytes, CL = 64 bytes
measured cpu frequency ~= 3368.262330
using 20 random witnesses for Rabin-Miller PRP checks
===============================================================
======= Welcome to YAFU (Yet Another Factoring Utility) =======
======= [EMAIL="bbuhrow@gmail.com"]bbuhrow@gmail.com[/EMAIL] =======
======= Type help at any time, or quit to quit =======
===============================================================
cached 78498 primes. pmax = 999983

>> factor(195655305149713288154123188773949297146841344810189391089778259859470761448147802086056459550628436477448302200577)
fac: factoring 195655305149713288154123188773949297146841344810189391089778259859470761448147802086056459550628436477448302200577
[COLOR=red]fac: using pretesting plan: deep[/COLOR]
[COLOR=red]fac: using tune info for qs/gnfs crossover[/COLOR]
div: primes less than 10000
fmt: 100 iterations
rho: x^2 + 3, starting 100 iterations on C114
rho: x^2 + 2, starting 100 iterations on C114
rho: x^2 + 1, starting 100 iterations on C114
pm1: starting B1 = 150K, B2 = gmp-ecm default on C114
ecm: 7/30 curves on C81, B1=2K, B2=gmp-ecm default
ecm: 22/22 curves on C69, B1=2K, B2=gmp-ecm default
ecm: 2/74 curves on C69, B1=11K, B2=gmp-ecm default
[COLOR=red]fac: factoring 228436888635662051737672282421311[/COLOR]
[COLOR=red]fac: using pretesting plan: normal[/COLOR]
[COLOR=red]fac: no tune info: using qs/gnfs crossover of 95 digits[/COLOR]
div: primes less than 10000
fmt: 1000000 iterations
rho: x^2 + 3, starting 1000 iterations on C33
rho: x^2 + 2, starting 1000 iterations on C33
rho: x^2 + 1, starting 1000 iterations on C33
pm1: starting B1 = 150K, B2 = gmp-ecm default on C33
ecm: 0/30 curves on C33, B1=2K, B2=gmp-ecm default
[COLOR=red]fac: factoring 2583536085788343611[/COLOR]
[COLOR=red]fac: using pretesting plan: normal[/COLOR]
[COLOR=red]fac: no tune info: using qs/gnfs crossover of 95 digits[/COLOR]
div: primes less than 10000
fmt: 1000000 iterations
rho: x^2 + 3, starting 1000 iterations on C19
rho: x^2 + 2, starting 1000 iterations on C19
rho: x^2 + 1, starting 1000 iterations on C19
pm1: starting B1 = 150K, B2 = gmp-ecm default on C19
ecm: 1/30 curves on C19, B1=2K, B2=gmp-ecm default
Total factoring time = 0.0240 seconds
Total factoring time = 0.0510 seconds
Total factoring time = 0.3110 seconds

***factors found***
P13 = 2657885582579
P15 = 588767351145079
P54 = 547325133126275165922253050493766036856888494139235427
P14 = 88420243050701
P9 = 314029091
P10 = 8227059721
ans = 1[/CODE]

Note the highlighted sections - the program seems to forget what is in the yafu.ini file when it starts again!
Is this the expected behaviour or a bug?

This is on a windows 7.1 machine, if that makes a difference.

A small thing that could be wished for when it comes to the Yafu output.

When finishing up a factorization I may receive a line such as this:

Aborting...
ecm: 42/904 curves on C142, B1=1M, B2=gmp-ecm default, ETA: 1.62 hrs

***factors found***

P23 = 14388029394339866454181
P34 = 1060364486115069441191164331606927

***co-factor***
C142 = 3056163545298800158466186774022368133068016379503393272824610897858902263
463782869792447400420402750642645810331052346695783446146155176604159


[url]http://factordb.com/index.php?id=1100000000766387041[/url]


If a blank line could be inserted in the output, it would be easier to report the individual factors.

I want to know that the report is complete, but for now I will have to mark the single line, copy it and then press carriage return manually. Of course I could report both factors at the same time, but in any case a carriage return needs to be added in order to finish a line.

Therefore, a patch could be added here, more for simplicity and ease of use rather than clarity.

Select the factors in their entirety, without selecting the equals sign. Now paste into the factordb "report factors" box. They will automatically be on different lines.

Thank you for that information.

I will make a note of it here.

Also, if you notice Dubslow's original post, you may also be get to this by using Yafu
if you happen to be curious about things.

[url]http://factordb.com/index.php?id=1100000000766401202[/url]

I get a crash with Yafu 1.34 using the following command

[code]
yafu "nfs(2196940604012711320004471908473775351297134659390227237136233264506968622288346446220877771181454955472133438440586392140297383446237820309950095296878156117919090513)" -v
[/code]

Consistent on various flavors of Windows, both 32 and 64 bit. It is a composite cofactor of the xyyxf number C166_148_128.

May be a repeat of a bug reported earlier, not really sure.

Crash when the name of the logfile is too long: [code]
$ "/home/chris/yafu/yafu" 'siqs(93451347628425346579303278899392351021992509207379796205743271284749984900563)' -v -p -logfile m99-231249749008564891846452398429823351310239794671906472490432715926072893930573350580185845652491139.
*** buffer overflow detected ***: /home/chris/yafu/yafu terminated
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(__fortify_fail+0x5c)[0x7f735b01c5cc]
/lib/x86_64-linux-gnu/libc.so.6(+0x110560)[0x7f735b01b560]
/home/chris/yafu/yafu[0x40e31a]
/home/chris/yafu/yafu[0x40e426]
/home/chris/yafu/yafu[0x4050bd]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5)[0x7f735af2cea5]
/home/chris/yafu/yafu[0x4055b5]
======= Memory map: ========
00400000-00560000 r-xp 00000000 08:01 5386358 /home/chris/yafu/yafu
0075f000-00760000 r-xp 0015f000 08:01 5386358 /home/chris/yafu/yafu
00760000-00771000 rwxp 00160000 08:01 5386358 /home/chris/yafu/yafu
00771000-00779000 rwxp 00000000 00:00 0
02671000-02692000 rwxp 00000000 00:00 0 [heap]
7f735acf5000-7f735ad09000 r-xp 00000000 08:01 12193428 /lib/x86_64-linux-gnu/libgcc_s.so.1
7f735ad09000-7f735af09000 ---p 00014000 08:01 12193428 /lib/x86_64-linux-gnu/libgcc_s.so.1
7f735af09000-7f735af0a000 r-xp 00014000 08:01 12193428 /lib/x86_64-linux-gnu/libgcc_s.so.1
7f735af0a000-7f735af0b000 rwxp 00015000 08:01 12193428 /lib/x86_64-linux-gnu/libgcc_s.so.1
7f735af0b000-7f735b0c9000 r-xp 00000000 08:01 12193403 /lib/x86_64-linux-gnu/libc-2.17.so
7f735b0c9000-7f735b2c8000 ---p 001be000 08:01 12193403 /lib/x86_64-linux-gnu/libc-2.17.so
7f735b2c8000-7f735b2cc000 r-xp 001bd000 08:01 12193403 /lib/x86_64-linux-gnu/libc-2.17.so
7f735b2cc000-7f735b2ce000 rwxp 001c1000 08:01 12193403 /lib/x86_64-linux-gnu/libc-2.17.so
7f735b2ce000-7f735b2d3000 rwxp 00000000 00:00 0
7f735b2d3000-7f735b3d6000 r-xp 00000000 08:01 12193451 /lib/x86_64-linux-gnu/libm-2.17.so
7f735b3d6000-7f735b5d6000 ---p 00103000 08:01 12193451 /lib/x86_64-linux-gnu/libm-2.17.so
7f735b5d6000-7f735b5d7000 r-xp 00103000 08:01 12193451 /lib/x86_64-linux-gnu/libm-2.17.so
7f735b5d7000-7f735b5d8000 rwxp 00104000 08:01 12193451 /lib/x86_64-linux-gnu/libm-2.17.so
7f735b5d8000-7f735b5f0000 r-xp 00000000 08:01 12193515 /lib/x86_64-linux-gnu/libpthread-2.17.so
7f735b5f0000-7f735b7ef000 ---p 00018000 08:01 12193515 /lib/x86_64-linux-gnu/libpthread-2.17.so
7f735b7ef000-7f735b7f0000 r-xp 00017000 08:01 12193515 /lib/x86_64-linux-gnu/libpthread-2.17.so
7f735b7f0000-7f735b7f1000 rwxp 00018000 08:01 12193515 /lib/x86_64-linux-gnu/libpthread-2.17.so
7f735b7f1000-7f735b7f5000 rwxp 00000000 00:00 0
7f735b7f5000-7f735b862000 r-xp 00000000 08:01 11017595 /usr/local/lib/libgmp.so.10.1.3
7f735b862000-7f735ba61000 ---p 0006d000 08:01 11017595 /usr/local/lib/libgmp.so.10.1.3
7f735ba61000-7f735ba62000 r-xp 0006c000 08:01 11017595 /usr/local/lib/libgmp.so.10.1.3
7f735ba62000-7f735ba6b000 rwxp 0006d000 08:01 11017595 /usr/local/lib/libgmp.so.10.1.3
7f735ba6b000-7f735ba8e000 r-xp 00000000 08:01 12193377 /lib/x86_64-linux-gnu/ld-2.17.so
7f735bb6a000-7f735bc6c000 rwxp 00000000 00:00 0
7f735bc8a000-7f735bc8d000 rwxp 00000000 00:00 0
7f735bc8d000-7f735bc8e000 r-xp 00022000 08:01 12193377 /lib/x86_64-linux-gnu/ld-2.17.so
7f735bc8e000-7f735bc90000 rwxp 00023000 08:01 12193377 /lib/x86_64-linux-gnu/ld-2.17.so
7fffe908e000-7fffe90af000 rwxp 00000000 00:00 0 [stack]
7fffe91fe000-7fffe9200000 r-xp 00000000 00:00 0 [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
Aborted
[/code]
If i shorten the name of the logfile it works OK: [code]
$ "/home/chris/yafu/yafu" 'siqs(93451347628425346579303278899392351021992509207379796205743271284749984900563)' -v -p -logfile m99-23124.log


03/25/15 14:22:46 v1.34.5 @ 4core, System/Build Info:
Using GMP-ECM, Powered by GMP
detected Intel(R) Core(TM) i5-3570 CPU @ 3.40GHz
detected L1 = 32768 bytes, L2 = 6291456 bytes, CL = 64 bytes
measured cpu frequency ~= 3392.281750
using 1 random witnesses for Rabin-Miller PRP checks

===============================================================
======= Welcome to YAFU (Yet Another Factoring Utility) =======
======= bbuhrow@gmail.com =======
======= Type help at any time, or quit to quit =======
===============================================================
cached 78498 primes. pmax = 999983


>>
starting SIQS on c77: 93451347628425346579303278899392351021992509207379796205743271284749984900563
[/code]
It's easy to bypass it now I know what causes the crash. So no rush to fix.

Chris

[QUOTE=swellman;398529]I get a crash with Yafu 1.34 using the following command

[code]
yafu "nfs(2196940604012711320004471908473775351297134659390227237136233264506968622288346446220877771181454955472133438440586392140297383446237820309950095296878156117919090513)" -v
[/code]

Consistent on various flavors of Windows, both 32 and 64 bit. It is a composite cofactor of the xyyxf number C166_148_128.

May be a repeat of a bug reported earlier, not really sure.[/QUOTE]

It seems to work in linux, which isn't entirely helpful to your issue. Can you provide more information about where exactly it crashes (e.g., a screenshot)?

[QUOTE=chris2be8;398607]Crash when the name of the logfile is too long: [/QUOTE]

And we have a new contender for "worse-abuse-of-a-feature" :smile:

See also: [url]http://www.mersenneforum.org/showpost.php?p=147070&postcount=3[/url]

[QUOTE=bsquared;398612]It seems to work in linux, which isn't entirely helpful to your issue. Can you provide more information about where exactly it crashes (e.g., a screenshot)?[/QUOTE]

Sorry I didn't expand - this seems to be the same bug behavior I reported in [url=http://www.mersenneforum.org/showpost.php?p=385248&postcount=300]this post[/url]. Lots of polys scroll by, then yafu crashes at the final "m=..." line of the last polynomial. It does not seem to attempt to evaluate the polynomials nor start the test sieving routine.

A generic windows error message pops up from the OS, saying "yafu.exe has encountered a problem and needs to close. We are sorry for the inconvenience."

The error report itself is equally unhelpful. "Error signature AppName: yafu.exe AppVer: 0.0.0.0 ModName: yafu.exe
ModVer: 0.0.0.0 Offset: 000deccc".


Can anyone else confirm this crash in Windows?