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2004-03-26, 17:14   #34
wblipp

"William"
May 2003
New Haven

32·263 Posts

Quote:
 Originally Posted by ET_ Now a question: I have a batch version of this program, and a list of about 3300 prime exponents starting from 3321928241,1,50 and ending with 3321999991,1,50 to feed it.
I'm attracted by the whimsical nature of starting a project that there is no hope of finishing. But not sufficiently attracted to put serious computing power towards it. I envision using an old Pentium-Pro 180 to gradually advance a single exponent. If there is no objection, I'll work on 3321928219.

William

2004-03-26, 17:18   #35
ET_
Banned

"Luigi"
Aug 2002
Team Italia

52×193 Posts

Quote:
 Originally Posted by wblipp I'm attracted by the whimsical nature of starting a project that there is no hope of finishing. But not sufficiently attracted to put serious computing power towards it. I envision using an old Pentium-Pro 180 to gradually advance a single exponent. If there is no objection, I'll work on 3321928219. William
That's OK for me.

Then I will co-moderate LMH > 79,2 Project, eventually giving a small boost to the search

Luigi

2004-03-27, 12:43   #36
wblipp

"William"
May 2003
New Haven

32·263 Posts

Quote:
 Originally Posted by ET_ I say HERE it is.
How do I set this up to work on "my" number? Does it use worktodo.ini?

William

2004-03-27, 16:47   #37
ET_
Banned

"Luigi"
Aug 2002
Team Italia

52×193 Posts

Quote:
 Originally Posted by wblipp How do I set this up to work on "my" number? Does it use worktodo.ini? William
No it doesn't.

When you run ./factor3_1 it asks for the exponent you want to run, the start and the stop bit. If you stop the program then restart it with the -r parameter, and it will reload its status.txt file.

Code:
\$ ./factor3_1

Please enter the exponent to be factored: 2^3321928219

Now enter start bit depth   : 1
Finally enter end bit depth : 67

Sieving from 2^2 up to 2^67...
HTH...

Luigi

2004-03-27, 17:18   #38
wblipp

"William"
May 2003
New Haven

32×263 Posts

Quote:
 Originally Posted by ET_ When you run ./factor3_1 it asks for the exponent you want to run
I tried "factor3_1 /?" and "factor3_1 3321928219" but I hadn't tried just plain "factor3_1". Thanks.

William

2004-03-27, 18:54   #39
ET_
Banned

"Luigi"
Aug 2002
Team Italia

12D916 Posts

Quote:
 Originally Posted by wblipp I tried "factor3_1 /?" and "factor3_1 3321928219" but I hadn't tried just plain "factor3_1". Thanks. William
My fault... I only tested -r and -h switches

Luigi

 2004-03-31, 16:32 #40 wblipp     "William" May 2003 New Haven 32·263 Posts I left factor3_1 running while I was away, and the computer was rebooted in my absence. I used the resume flag to restart the process, and it appears to be continuing from where it was shutdown. But can I be sure it didn't find any factors while I was away? Or do I need to repeat the search?
2004-03-31, 17:28   #41
ET_
Banned

"Luigi"
Aug 2002
Team Italia

52·193 Posts

Quote:
 Originally Posted by wblipp I left factor3_1 running while I was away, and the computer was rebooted in my absence. I used the resume flag to restart the process, and it appears to be continuing from where it was shutdown. But can I be sure it didn't find any factors while I was away? Or do I need to repeat the search?
You can be sure.

Every time the program finds a factor, it writes a line on the screen AND on result.txt file. You only have to check out that file to be sure...

Happy hunting!

Luigi

 2004-03-31, 18:37 #42 Thomas11     Feb 2003 22×32×53 Posts Hi Luigi, I compiled your factor3_1.c under Linux but I always get a segmentation fault when I try to start it. It asks for the exponent, the starting and ending bit, but then it stops with that segmentation fault. I haven't looked very much into the internals of your code. May be some of the GMP-arrays are too small or some pointers are computed wrong. Under some circumstances this could cause problems under Windows too... Has anyone else tested your program under Linux and/or other Unix-like operating systems? -- Thomas
2004-03-31, 18:56   #43
ET_
Banned

"Luigi"
Aug 2002
Team Italia

482510 Posts

Quote:
 Originally Posted by Thomas11 Hi Luigi, I compiled your factor3_1.c under Linux but I always get a segmentation fault when I try to start it. It asks for the exponent, the starting and ending bit, but then it stops with that segmentation fault. I haven't looked very much into the internals of your code. May be some of the GMP-arrays are too small or some pointers are computed wrong. Under some circumstances this could cause problems under Windows too... Has anyone else tested your program under Linux and/or other Unix-like operating systems? -- Thomas
I did :-)))

Factor3_1.c has been successfully compiled under Linux Mandrake 9.2, with GMP 4.1.2 and a Xeon PIII @ 500 MHz. I noticed no malfunctioning at all.

I myself ran across that "segmentation fault" problem. In my case was a matter of libraries' path. Anyway, I will re-check my source code and re-compile to see what happened, then I will send here a (hopefully working) gzipped copy tomorrow as soon as I get to my office.

Luigi

 2004-04-01, 01:54 #44 ColdFury     Aug 2002 26×5 Posts GMP allocates space for the numbers on the stack, instead of the heap. If you make a number that's too large, you'll run out of stack space and get a segfault. They do this for speed. If you want numbers to be allocated from the heap, you have to specify it when you compile the library.

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