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-   -   Phi.exe (https://www.mersenneforum.org/showthread.php?t=9496)

henryzz 2007-10-25 16:17

windows vista ultimate

Andi47 2007-10-25 17:13

[QUOTE=Andi47;117034]I am getting this error too - I am using Windows XP professional.[/QUOTE]

When I try to run it in msys / mingw, I get "./phi: Permission denied."

smh 2007-10-25 17:52

[QUOTE=Andi47;117034]I am getting this error too - I am using Windows XP professional.[/QUOTE]I'm on Vista and get a popup "phi.exe is not a valid Win32 application".After that, i get a "Access is denied."

akruppa 2007-10-25 22:35

1 Attachment(s)
I have two cross-compilers installed, not sure what the difference is. There's a binary from the other one, and not stripped of symbols this time. Maybe this works.

Gah, upload limit is ~250k for .zip files. For .pdf it's larger, so I'm renaming the file... simply rename back to .zip.

Alex

Andi47 2007-10-26 07:09

Now it works under windows, I have not (yet?) tested if the poly works with msieve.

Just one question: phi.exe outputs SNFS polynomials, does it make sense to enter this into msieve, which does GNFS?

akruppa 2007-10-26 11:35

SNFS and GNFS differ only in how the polynomial is selected. The fact that msieve does GNFS means that it has code that can find reasonably good polynomials for numbers not of a simple algebraic form. However, if you supply a polynomial made by other means, i.e. with pencil and paper or with phi, msieve can skip the polynomial selection step, will sieve away just as happily and finish the factorization.

Alex

henryzz 2007-10-26 17:02

what limits are there on what n and x i can input it seems to always crash for me

Andi47 2007-10-27 06:18

[QUOTE=akruppa;117114]SNFS and GNFS differ only in how the polynomial is selected. The fact that msieve does GNFS means that it has code that can find reasonably good polynomials for numbers not of a simple algebraic form. However, if you supply a polynomial made by other means, i.e. with pencil and paper or with phi, msieve can skip the polynomial selection step, will sieve away just as happily and finish the factorization.

Alex[/QUOTE]

Thanks.

How can I feed the polynomial into msieve? (I must do something wrong or miss something, as it always says that it failed to read the poly)

jasonp 2007-10-28 04:04

[QUOTE=Andi47;117178]
How can I feed the polynomial into msieve? (I must do something wrong or miss something, as it always says that it failed to read the poly)[/QUOTE]
Can you give an example? The factor base file contains the number to be factored, and this has to match the number given on the command line (or from a file like worktodo.ini). This number should not include any small factors that are known, otherwise the library will find the small factors and give up.

Also, you should be using GGNFS for the sieving, it would finish about 5x faster.

Andi47 2007-10-28 06:54

[QUOTE=jasonp;117217]Can you give an example? The factor base file contains the number to be factored, and this has to match the number given on the command line (or from a file like worktodo.ini). This number should not include any small factors that are known, otherwise the library will find the small factors and give up.

Also, you should be using GGNFS for the sieving, it would finish about 5x faster.[/QUOTE]

An example, just for testing if it works, I will definitely NOT finish this factorization:

phi.exe output for 3,527-:
[code]N 5466315818570157744600674404470135554420684751405676880272078210385283404043543171940308633417556688973629087522011173645136493977169190093057301775731456787243
R0 125236737537878753441860054533045969266612127846243
R1 -1
A0 -1
A1 0
A2 0
A3 0
A4 0
A5 9
[/code]

Repeat, I will definitely NOT finish this or even run it any longer than a few minutes, I just wanted to test if it works.

GGNFS: I tried to install GGNFS on my computer last winter, but due to lack of Linux knowledge I did not succeed to get it to run in a windows / mingw (msys) environment.

jasonp 2007-10-28 13:45

[QUOTE=Andi47;117221]An example, just for testing if it works[/QUOTE]
Paste this output into msieve.fb, copy the first line to worktodo.ini (without the 'N ') and run 'msieve -v -ns'. It starts sieving for me, though the automatically chosen parameters are very suboptimal for such a larger SNFS job


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