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Subject: Re: right now, at this very moment wac 141?

Author: Stuart Cracraft

Date: 19:45:47 09/28/04

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On September 28, 2004 at 13:39:44, Henk Bossinade wrote:

>On September 28, 2004 at 01:04:52, Stuart Cracraft wrote:
>
>>On September 26, 2004 at 15:53:53, David B Weller wrote:
>>
>>> 2   -223   0.01       375 {12}  Kf1 Re2
>>> 3   -205   0.02      1061 {13}  Kf1 Re2 Kg1
>>>4r1k1/p1qr1p2/2pb1Bp1/1p5p/3P1n1R/1B3P2/PP3PK1/2Q4R w - - bm Qxf4; id "WAC.141";
>>>
>>> 4   -239   0.05      3815 {18}  Kf1 Re2 Qc3 b4
>>> 5+  -199   0.18     16983 {23}  Kf1
>>> 5   -185   0.35     36630 {23}  Kf1 a5 Qb1 a4 Bc2
>>> 6   -206   0.86     91286 {25}  Kf1 Re2 Qb1 Rd2 Kg1 Nd3
>>> 7   -175   2.48    248962 {27}  Kf1 Re2 Qb1 Rd2 Qc1 Rd3 Be5 Bxe5 dxe5
>>> 8+  -135   7.29    832695 {29}  Qxf4
>>> 8    299   9.88   1150509 {29}  Qxf4 Bxf4 Rxh5 gxh5 Rxh5 Bh6 Rxh6 Qh2+ Rxh2
>>> 9    299  13.58   1503202 {29}  Qxf4 Bxf4 Rxh5 gxh5 Rxh5 Bh6 Rxh6 Qh2+ Rxh2
>>>10+   339  25.34   2971184 {30}  Qxf4
>>>Knps: 94[r=745471 q=4971821(86%)]Qxf4
>>>fh=83% bf=3.17
>>>ext: ck=107333 p7=1950 mt=1051 1r=1488 re=2311 delay=0 good=0
>>>red: nm=93529 fc=16253558 zg=0
>>>ht=88%
>>>move c1f4
>>>
>>David,
>>
>>Hey that's great -- only 7.29 seconds. Congratulations.
>>
>>Okay, so what are the goods? How did you do it?
>>
>>Can you repost your web URL for the GES that did the above and
>>cite the relevant portions of code you believe are responsible for
>>your superior time for Qxf4!
>>
>>Stuart
>
>Here's my wac141 with mate threat:
>
>        time    score     nodes   pv
>  5.    0.89    -70       84104   Kg2f1 Re8e2 Qc1b1 Re2d2 Qb1c1 Rd2e2 Qc1b1
>  6     4.51    -70      470874   Kg2f1 Re8f8 Qc1b1 Nf4d5 Bf6g5 Qc7c8 Qb1e1
>  6     7.27    -69      762159   Qc1xNf4 Bd6xQf4 Rh4xPh5 Pg6xRh5 Rh1xPh5 Bf4h6
>  6.    7.27    -69      762159   Qc1xNf4 Bd6xQf4 Rh4xPh5 Pg6xRh5 Rh1xPh5 Bf4h6
>  7     9.21    -69     1026574   Qc1xNf4 Bd6xQf4 Rh4xPh5 Pg6xRh5 Rh1xPh5 Bf4h6
>  7.   11.86    -69     1259450   Qc1xNf4 Bd6xQf4 Rh4xPh5 Pg6xRh5 Rh1xPh5 Bf4h6
>  8    32.27     ++     3422740   Qc1xNf4 Bd6xQf4 Rh4xPh5 Pg6xRh5 Rh1xPh5 Bf4h6
>  8    83.38    260     9293559   Qc1xNf4 Bd6xQf4 Rh4xPh5 Pg6xRh5
>  8.   87.74    260     9778848   Qc1xNf4 Bd6xQf4 Rh4xPh5 Pg6xRh5
>
>here without:
>
>  7.   13.49    -70     1458658   Kg2f1 Re8f8 Qc1b1
>  8    90.45    -70     9788445   Kg2f1 Pa7a5 Rh1g1
>  8   112.56     ++    11842418   Qc1xNf4 Bd6xQf4 Rh4xPh5 Pg6xRh5 Rh1xPh5
>  8   157.69    260    16856578   Qc1xNf4 Bd6xQf4 Rh4xPh5 Pg6xRh5
>  8.  160.32    260    17120337   Qc1xNf4 Bd6xQf4 Rh4xPh5 Pg6xRh5
>
>I noticed in the search() code you posted that you return a mate score like
>this:
>
>  if (legals == 0) {
>    if (checked) {
>       best = -MATE+depth;
>    } else {
>       best = STALEMATE;
>    }
>
>and your mate threat code looks like this:
>
>  if (!extended && value == -MATE+ply+2) {
>//    printf("mate threat:\n");listmvs(hist);pbd(bd);getchar();
>    extend=1;
>    extended=1;
>    depth++;
>  }
>
>I think you should use either depth/depth or ply/ply but not like it is.

I've chosen ply/ply. I was told ply is better since it returns a lower
value for a mate discovered higher in the tree. Not sure if depth/depth
or ply/ply minimizes the moves to mate. Thought depth/depth did that...

>Also instead of 'value == -MATE+ply+2' you can try 'value <= -MATE+maxply'
>

I've tried that in the past. It blows up my search.

>Some other things:
>
> - uncomment the printf line above and make sure you get the correct threat
>   positions with white rook on open h file
> - for debugging purposes get rid of some possibly distorting variables:
>
>    - use only material evaluation (it's a purely tactical position)
>    - use unlimited extensions
>
>hb



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