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Hi all,

can anyone post a really working link to the sources (TBGEN.ZIP) of the old 5-men Nalimov tablebase generator (provided Eugene Nalimov still allows reading them)?

I mean the generator itself, not only the probing code (which is indirectly available through Crafty and others).

IIRC they had been online a while ago at least at Robert Hyatt's page but now I don't find them anymore. Tried also many Google links, everything seems dead.

Please, no "Why do you need the generator, you can download all (3-4-5-)6-men TBs from XY" answers, because my main intention is not having the TBs but looking at the generator source itself. I already had written an own 4-men generator but it was very inefficient, and last year I lost the sources unfortunately. Now I want to restart somehow (not by "cloning", of course), just for my own fun at the moment.

Any help would be appreciated. You may also send me an email (see bottom of the "Surprise" homepage).

Sven

The Yahoo! chess-engines group has the tbgen source, in the Files section. You have to sign up with Yahoo! first and join the chess-engines group before you can access the file area.

Tony

Tbgen.zip

Jim.

Thanks Tony and Jim, that's what I looked for!
Sven

Hmmmm ... @Jim: this Tbgen.zip seems to be incomplete, at least tbdecode.c is missing (it is included from tbindex.cpp which in turn is included from Tbgen.cpp).

@Tony: I can't find a Yahoo! group named "chess-engines". I logged in with my Yahoo ID and searched for groups with "chess-engines", "chess engines", or just "chess", but I only found "chessdatabase", "Chess_Engines_Testing", "Chess_Library", and "Chess_Improvement". Did you mean one of these? Or what am I doing wrong?

Any ideas?

Sven

Sven Schüle wrote:...I can't find a Yahoo! group named "chess-engines". ...

Any ideas?

http://groups.yahoo.com/group/chess-engines/

Volker

Now I got a compiling version, thanks Volker!

The "chess-engines group" version seems to be the very old one from 1998 but I think it's sufficient for now to try to understand the basics.

Nevertheless I would like to know whether someone has a newer version which is complete (5- or 6-men, does not matter).

Regards,
Sven

If you are interested in the workings of TB generators in general, I have a simple but fast one for Pawn-less endings on my web-site:

http://home.hccnet.nl/h.g.muller/5men13.c

with some descriptions here.

It cannot do 6 men unless you have an unreasonably big 64-bit system, but it builds a typical 5-men TB in ~240 sec on my 1.3GHz Celeron M. Adapting it to handle Pawns would make it both simpler (you would hardly have to worry about symmetry) and more complicated (you would have to find the DTM of promoted positions from an existing TB).

Here is my output on 2.2 GHz AMD Athlon

Code: Select all

410020 411000
KBB_KN
  0.         0         0  40193555         0   4.984   4.984   0.000
  0.     16488         0  40193555 1310904372  38.126   4.984  33.142
  1.     21244    437907     69184         0  38.235   5.093  33.142
  2.     17139    609625    102148         0  38.376   5.234  33.142
  3.     12928    511023     84098         0  38.501   5.359  33.142
  4.     11580    420021     65830         0  38.610   5.468  33.142
  5.     14292    522067     78481         0  38.735   5.593  33.142
  6.     19760    633695     91324         0  38.860   5.718  33.142
  7.     28018   1011420    138491         0  39.048   5.906  33.142
  8.     43974   1573161    202927         0  39.298   6.156  33.142
  9.     62265   2567323    318043         0  39.626   6.484  33.142
 10.     98110   4052112    476243         0  40.079   6.937  33.142
 11.    140681   6597443    747124         0  40.704   7.562  33.142
 12.    210965   9763684   1058627         0  41.532   8.390  33.142
 13.    284693  13622055   1446126         0  42.595   9.453  33.142
 14.    399918  18804181   1945747         0  43.939  10.797  33.142
 15.    562300  22971056   2330980         0  45.548  12.406  33.142
 16.    769116  27357987   2729968         0  47.439  14.297  33.142
 17.    934463  28350426   2812378         0  49.470  16.328  33.142
 18.    842421  20295735   2055593         0  51.298  18.156  33.142
 19.    630337  11306075   1270277         0  52.751  19.609  33.142
 20.    538938   8133794    948144         0  53.986  20.844  33.142
 21.    437436   5464947    629584         0  55.048  21.906  33.142
 22.    347383   3865877    441624         0  55.970  22.828  33.142
 23.    270176   2838915    328017         0  56.783  23.641  33.142
 24.    218373   2152535    251754         0  57.455  24.313  33.142
 25.    197301   1860859    221472         0  58.033  24.891  33.142
 26.    196877   1829374    218410         0  58.580  25.438  33.142
 27.    211266   2000788    241061         0  59.127  25.985  33.142
 28.    227531   2172555    258152         0  59.720  26.578  33.142
 29.    231384   2252949    265900         0  60.330  27.188  33.142
 30.    228903   2292859    266158         0  60.939  27.797  33.142
 31.    227364   2233054    257984         0  61.564  28.422  33.142
 32.    230553   2278789    257777         0  62.189  29.047  33.142
 33.    220597   2290666    257647         0  62.799  29.657  33.142
 34.    212820   2215190    246608         0  63.408  30.266  33.142
 35.    195737   2120278    235145         0  63.986  30.844  33.142
 36.    192307   2012627    220607         0  64.549  31.407  33.142
 37.    199594   2037167    220562         0  65.080  31.938  33.142
 38.    212780   2161523    231203         0  65.627  32.485  33.142
 39.    243478   2384707    251108         0  66.189  33.047  33.142
 40.    278943   2742042    286071         0  66.799  33.657  33.142
 41.    304942   3080707    321358         0  67.502  34.360  33.142
 42.    312444   3242585    340116         0  68.252  35.110  33.142
 43.    310188   3212660    335360         0  69.017  35.875  33.142
 44.    297251   3087271    321540         0  69.768  36.626  33.142
 45.    280541   2901608    299451         0  70.502  37.360  33.142
 46.    263536   2705134    276344         0  71.221  38.079  33.142
 47.    243629   2577689    261634         0  71.893  38.751  33.142
 48.    218826   2383845    241019         0  72.518  39.376  33.142
 49.    188894   2048047    207699         0  73.096  39.954  33.142
 50.    151543   1656334    168759         0  73.596  40.454  33.142
 51.    126050   1320397    133469         0  74.018  40.876  33.142
 52.    117183   1189388    119687         0  74.393  41.251  33.142
 53.    114785   1137160    113534         0  74.736  41.594  33.142
 54.    122978   1117494    112886         0  75.080  41.938  33.142
 55.    144843   1152292    115806         0  75.440  42.298  33.142
 56.    211461   1416954    141959         0  75.846  42.704  33.142
 57.    332282   2058101    203047         0  76.361  43.219  33.142
 58.    468435   3074486    300858         0  77.174  44.032  33.142
 59.    580855   4213644    405834         0  78.065  44.923  33.142
 60.    695064   5224735    499595         0  79.143  46.001  33.142
 61.    817064   6326572    596766         0  80.362  47.220  33.142
 62.    977336   7523834    700212         0  81.752  48.610  33.142
 63.   1212186   8858766    806092         0  83.299  50.157  33.142
 64.   1509309  10579075    944487         0  85.049  51.907  33.142
 65.   1792981  11939008   1046032         0  87.034  53.892  33.142
 66.   1965032  12425970   1068129         0  89.096  55.954  33.142
 67.   1992500  11973805   1014735         0  91.174  58.032  33.142
 68.   1848015  10609999    891679         0  93.128  59.986  33.142
 69.   1642726   8948397    748904         0  94.909  61.767  33.142
 70.   1409910   7190366    601680         0  96.487  63.345  33.142
 71.   1135315   5331289    444707         0  97.831  64.689  33.142
 72.    772689   3326134    276383         0  98.862  65.720  33.142
 73.    369030   1409251    116513         0  99.534  66.392  33.142
 74.     98149    314052     26218         0  99.862  66.720  33.142
 75.     11690     30784      2919         0  99.987  66.845  33.142
 76.      3850      8818       966         0 100.034  66.892  33.142
 77.       916      2622       300         0 100.065  66.923  33.142
 78.        96       613        67         0 100.097  66.955  33.142
 79.         0         0         0         0 100.112  66.970  33.142
 78958876 marked win.wtm
384348377 labeled potential win(n).btm
1310904372 checked
314204330 2377132303
Press any key to continue . . .


Yes, that is how it is supposed to look. The meaning of the columns is:

1 - DTM (0 = checkmated)
2 - Number of positions with this DTM for black to move
3 - Number of positions with this DTM+1 for white to move
4 - Number of btm positions that got their non-losing-move count reduced or set
5 - Number of moves tested for being losing from btm posiitons
6 - total cumulative execution time in sec
7 - cumulative time spent in finding 2 generations of pre-decessor positions of the current DTM
8 - cumulative time spent in verifying potentially lost btm positions

So for the KBBKN end-game the generation of the TB took 33 sec for counting the number of legal moves in all BTM positions, and 67 sec to determine all positions won for white and the DTM of all positions lost to black. Largest DTM was 78, and there were 96 (btm) positons that had this DTM.

Note the number of positions are those folded by symmetry, i.e. not corrected for the number of actual positions that correspond to the symmetry-reduced TB elements, and furthermore contain all subset end-games as well (so KBBK, KBKN, KBK, KKN and KK in this case). This makes them useless for comparing to other tablebase statistics, they only serve to see how your algorithm is progressing.

Meaningful statistics, corrected for symmetry and only including positons with the nominal piece makeup are written in a file 'report.txt' (but still have to be multiplied by 4).