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

Author: Uri Blass

Date: 13:21:43 09/29/04

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On September 28, 2004 at 22:45:47, Stuart Cracraft wrote:

>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.

I think that it is clear that extending every nate threat by a full ply will
blow your search.

If you do not use partial extensions then I suggest that you do not extend mate
threats unless  you have some conditions to extend them only near the root and
not every where.

Uri



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