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wblipp 2004-03-26 17:14

[QUOTE=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.[/QUOTE]

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

ET_ 2004-03-26 17:18

[QUOTE=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[/QUOTE]

That's OK for me.

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

Luigi

wblipp 2004-03-27 12:43

[QUOTE=ET_]I say HERE it is.[/QUOTE]

How do I set this up to work on "my" number? Does it use worktodo.ini?

William

ET_ 2004-03-27 16:47

[QUOTE=wblipp]How do I set this up to work on "my" number? Does it use worktodo.ini?

William[/QUOTE]

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^[I]3321928219[/I]

Now enter start bit depth : [I]1[/I]
Finally enter end bit depth : [I]67[/I]

Sieving from 2^2 up to 2^67...
[/code]

HTH...

Luigi

wblipp 2004-03-27 17:18

[QUOTE=ET_]When you run ./factor3_1 it asks for the exponent you want to run[/QUOTE]

I tried "factor3_1 /?" and "factor3_1 3321928219" but I hadn't tried just plain "factor3_1". Thanks.

William

ET_ 2004-03-27 18:54

[QUOTE=wblipp]I tried "factor3_1 /?" and "factor3_1 3321928219" but I hadn't tried just plain "factor3_1". Thanks.

William[/QUOTE]

My fault... I only tested -r and -h switches :redface:

Glad it now works. :smile:

Luigi

wblipp 2004-03-31 16:32

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?

ET_ 2004-03-31 17:28

[QUOTE=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?[/QUOTE]

You can be sure. :smile:

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... :rolleyes:

Happy hunting!

Luigi

Thomas11 2004-03-31 18:37

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

ET_ 2004-03-31 18:56

[QUOTE=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[/QUOTE]

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

ColdFury 2004-04-01 01:54

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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