Author: Michael Henderson
Date: 17:12:26 09/29/04
Go up one level in this thread
On September 29, 2004 at 19:32:27, Stuart Cracraft wrote: >On September 29, 2004 at 18:52:45, Michael Henderson wrote: > >>On September 29, 2004 at 17:29:57, Stuart Cracraft wrote: >> >>>On September 29, 2004 at 16:06:36, Uri Blass wrote: >>> >>>>On September 29, 2004 at 14:51:16, Dan Honeycutt wrote: >>>> >>>>>On September 29, 2004 at 14:16:23, Stuart Cracraft wrote: >>>>> >>>>>[snip] >>>>>> >>>>>>WAC 141 takes me a shade over 24,000,000 nodes, a fully completed 7 ply search, >>>>>>to find Qxf4 with all the above improvements, still the same amount of >>>>>>time as without: >>>>>> >>>>>>Alpha=-1332 Beta=-532 Maxdepth=9999999 MaxTime=1410065407 >>>>>> 1/11 g2f1 0.00 -953 945 g2f1 f4d5 >>>>>> g2f1 f4d5 >>>>>> 2/12 g2f1 0.01 -953 1653 >>>>>> g2f1 f4d5 c1g5 >>>>>> 3/12 g2f1 0.02 -953 5073 >>>>>> g2f1 f4d5 c1g5 d5f6 >>>>>> 4/20 g2f1 0.09 -953 19924 >>>>>> g2f1 f4d5 b3d5 c6d5 c1c7 d6c7 f1g1 >>>>>> 5/22 g2f1 0.71 -953 170357 >>>>>> g2f1 b5b4 b3a4 f4d5 f6g5 d5e7 >>>>>> 6/26 g2f1 2.85 -953 617222 >>>>>> g2f1 b5b4 mtmt >>>>>> 7/32> g2f1 56.60 -553 13644478 g2f1 e8c8 c1b1 f4d5 b1e4 d6b4 f6e5 c7b6 >>>>>> g2f1 e8c8 c1b1 f4d5 b1e4 d6b4 >>>>>> 7/34 c1f4 97.33 5113 24161497 c1f4 e8e6 f4g5 d7e7 b3e6 e7e6 h1d1 d6e7 f6e7 >>>>>> c1f4 e8e6 f4g5 d7e7 b3e6 e7e6 h1d1 >>>>>> 8/34 c1f4 115.59 5113 27838968 >>>>>> c1f4 e8e6 f4g5 d7e7 b3e6 e7e6 h1d1 >>>>>> 9/34> c1f4 197.37 5513 48705672 >>>>>> c1f4 e8e6 f4g5 d7e7 b3e6 e7e6 h1d1 mtmt >>>>>> 9/... still searching >>>>>> >>>>>>Stuart >>>>> >>>>>Doesn't look like the program has actually found Qxf4. e8e6 is not the next >>>>>move. >>>>> >>>>>Dan H. >>>> >>>>The next move is not important >>>> >>>>Every move is losing and the question what is the next move in the program pv is >>>>dependent on extensions. >>>> >>>>It is clear that too many extensions were used because the program needs so many >>>>nodes to finish depth 7 and the selctive depth is too high(depth 7/34). >>>> >>>>I believe that the recapture extension that is used is bad if it helps to solve >>>>the problem at depth 7 with so many nodes but the only test to be sure is games. >>>> >>>>Uri >>>>Uri >>> >>>I considered your last point as well and removed RECAP. The problem cannot >>>be resolved without it after 10+ minutes. With it, it solves at 95 seconds >>>at ply 7. >>> >>>My main search escape-from-checks and quiescence escape-from-checks are >>>unlimited. >>> >>>I do not search checking moves except in main search or unless a move >>>out of check in quiescence is a checking move. >>> >>>Stuart >> >>I think there is something wrong with your search. -953 is too large of a >>losing score for g2f1, it should be around -100 to -300. Can you post the >>complete variation that leads to this score? with Triangular array you can by >>not cutting off with a PV entry. h1d1 in the PV looks strange also. >> >>Recapture extension should not be helping you here, I believe. I don't think >>even captures are hiding anything useful. >> >>Michael > >I measure in millipawns so -953 is just under a pawn down for Kf1 >which is about the higher end of your range. > >In the printout, the first line is the triangular array variation >and the line immediately under it is the walk-the-pv-in-hash variation. >So for ply 7: > >>>>>> 7/34 c1f4 97.33 5113 24161497 c1f4 e8e6 f4g5 d7e7 b3e6 e7e6 h1d1 d6e7 f6e7 >>>>>> c1f4 e8e6 f4g5 d7e7 b3e6 e7e6 h1d1 > >The c1f4 e8e6 f4g5 d7e7 b3e6 e7e6 h1d1 d6e7 is triangular array pv. > >I have heard that said about recaptures but if I don't have it on it >fails. My recapture extension is: > >#ifdef RECAP > // Extend if a recapture > if (!extended && histptr >= 2 && hist[histptr-1].cap != 0 && > hist[histptr-2].cap != 0 && hist[histptr-1].to == hist[histptr-2].to >#ifdef NEVER > && ABS(hist[histptr-2].pc) == ABS(hist[histptr-1].cap) > && ABS(hist[histptr-2].cap) == ABS(hist[histptr-1].cap) >#endif > ) { > > recapext++; > extend+=1.00; > } > >I don't have the NEVER on as that limits the recaptures too severely. >By just limiting to two captures by any pieces to the same square >in the last two moves, without regards to the piece or the material, >that RECAP is what gets me WAC 141 at all. If I don't have it or have >it in that exact way as above, I don't get WAC 141 at all. With it >I get WAC 141 with or without my mate-threat at the same time interval >of 95-97 seconds. > >Stuart I suggest not doing any more testing until you find out why you can't solve WAC at all with reasonable, good extensions. I honestly think that is a serious bug. You need to strip down the search to something simple and easy to work with, to find out what is wrong. For example an engine with a captures only qsearch, plain alpha beta and mate threat extension only--easy enough to make and debug :) Michael
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