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[QUOTE=jcrombie;359292]You can sieve on two sides -- the 'algebraic' side and the 'rational' side. If your .poly file has "type: snfs" then the factMsieve.pl script will sieve on the 'rational' side. If your .poly file has "type: gnfs" then it sieves on the 'algebraic' side. I believe the .py script is just a straight port from the perl script, so this should also apply there.
<snip> [/QUOTE] I hate it when someone who is ignorant of the subject insists on posting misinformation. NFS sieves on BOTH SIDES. Didn't you read my prior post on this subject? You can read, can't you???? Within this very thread I already said that it sieves on BOTH sides. The only question is: On which side do we sieve with respect to the full lattice and on which side do we sieve with respect to the special-q sub-lattice? But both sides get sieved. [QUOTE] Hope that helps a bit:smile:. [/QUOTE] About as much as a toothache. |
[QUOTE=R.D. Silverman;359294]
The only question is: On which side do we sieve with respect to the full lattice and on which side do we sieve with respect to the special-q sub-lattice? But both sides get sieved. [/QUOTE] You are talking about different things. The OP asked about how to most effectively [B]use the tools[/B] and you answered with an introduction to how to implement a sieve. That is fine, and the resulting discussion is good, but I see no need to jump on someone's case when they are trying to answer the OP's [B]tool usage question.[/B] |
[QUOTE=bsquared;359296]You are talking about different things. The OP asked about how to most effectively [B]use the tools[/B] and you answered with an introduction to how to implement a sieve. That is fine, and the resulting discussion is good, but I see no need to jump on someone's case when they are trying to answer the OP's [B]tool usage question.[/B][/QUOTE]
You need to learn to read as well. The OP asked about how small to make the starting value for special_q. I replied with what I do. The OP then said he did not understand my reply. (#176) The rest followed. The OP's first post showed that he knew how to use the tool to set the starting q. The question was about its value. The reply I criticized was NOT about tool usage. It contained a blatantly false assertion about sieving on just one side. Such assertions make my job much harder, because I have to spend time to correct the misinformation. And this especially applies when the misinformation directly contradicts something that I said just a few posts earlier. |
[QUOTE=R.D. Silverman;359268]
huh? One allocates space for the table. If there are more primes to store than space allows one gets an overflow. Why is this a mystery? One can also get an "overflow" as the table starts to get full. If a collision occurs it has to be resolved. There are a variety of ways to do this. But once the table starts to get full one spends TOO MUCH TIME resolving the *()!#&*@#&* collisions. It isn't worth it. Yes. I could re-code to dynamically allocate more space for the table as it starts to get full. I never thought it worth the effort. [/QUOTE] OK, now I see what you mean. [QUOTE=R.D. Silverman;359268] Perhaps you might want to read "Development of the Number Field Sieve", by Lenstra et.al.? [/QUOTE] I read about that book (in this forum) I'm looking for it. [QUOTE=jcrombie;359292] ... If your .poly file has "type: snfs" then the factMsieve.pl script will sieve on the 'rational' side. If your .poly file has "type: gnfs" then it sieves on the 'algebraic' side. I believe the .py script is just a straight port from the perl script, so this should also apply there. ... [/QUOTE] No. It goes like this: [CODE] # factmsieve.py line 1672 siever_option = '-r' if lats_p['lss'] else '-a' siever_side = 'rational' if lats_p['lss'] else 'algebraic' [/CODE] If lss is set in the poly file => 'rational', otherwise 'algebraic'. However I have no idea what 'lss' is. A lot of things were said in the previous posts thank you all, I think I have to do my homework now :) I understand the theory behind NFS is far from being easy, but I'm willing to learn. However on the practical side I think there is a lack of information for someone who would like to start digging into the details instead of just running the script (which is pretty easy thanks to this[URL="http://gilchrist.ca/jeff/factoring/nfs_beginners_guide.html"] excellent page[/URL]). |
[QUOTE=R.D. Silverman;359301]The reply I criticized was NOT about tool usage. It contained
a blatantly false assertion about sieving on just one side. [/QUOTE] Where did he say "only one side"? I believe it is colloquial to say "algebraic side" when one means "special-q on the algebraic side". Nowhere can I see him say that only one side is sieved. |
[QUOTE=bsquared;359308]Where did he say "only one side"? I believe it is colloquial to say "algebraic side" when one means "special-q on the algebraic side". Nowhere can I see him say that only one side is sieved.[/QUOTE]
I quote: "You can sieve on two sides -- the 'algebraic' side and the 'rational' side. If your .poly file has "type: snfs" then the factMsieve.pl script will sieve on the 'rational' side. If your .poly file has "type: gnfs" then it sieves on the 'algebraic' side." This is clear. The post says that it sieves on one side depending on how the type is set. This is wrong. It sieves on both sides. "applying special_q" does NOT equal "sieve". |
[QUOTE=R.D. Silverman;359309]I quote:
This is wrong. It sieves on both sides. "applying special_q" does NOT equal "sieve".[/QUOTE] Thanks for pointing that out. I'll update my language from now on. |
[QUOTE=YuL;359302]
No. It goes like this: [CODE] # factmsieve.py line 1672 siever_option = '-r' if lats_p['lss'] else '-a' siever_side = 'rational' if lats_p['lss'] else 'algebraic' [/CODE]If lss is set in the poly file => 'rational', otherwise 'algebraic'. However I have no idea what 'lss' is. [/QUOTE] My guess: lss = 'lattice sieve side'. Look around a bit and you will see that it does actually mimic the perl script with regards to "type: snfs" vs. "type: gnfs". (It also apparently has an extra feature that allows the user to override the side :smile:) [QUOTE=YuL;359302] However on the practical side I think there is a lack of information for someone who would like to start digging into the details instead of just running the script (which is pretty easy thanks to this[URL="http://gilchrist.ca/jeff/factoring/nfs_beginners_guide.html"] excellent page[/URL]).[/QUOTE] Yes, sad but true. |
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[QUOTE=jcrombie;359462]
Yes, sad but true.[/QUOTE] There is a tex document in [URL="https://sourceforge.net/p/ggnfs/code/HEAD/tree/trunk/doc/ggnfs-doc/"]subfolder ggnfs-doc of ggnfs[/URL] written by Chris Monico, I converted it to pdf, it is a very interesting reading. Although it is way out of date there is a lot of useful information (see section 10 for info about the parameters in the poly file). Here is the pdf: |
Back on topic I'm reserving:
53^128+1 C182 76^124+1 C156 96^113+1 C156 (The last two by GNFS). Chris |
Time to reserve:
53^143+1 89^113+1 Chris |
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