Author: Robert Hyatt
Date: 07:18:08 01/14/01
Go up one level in this thread
On January 14, 2001 at 00:37:12, Christophe Theron wrote: >On January 14, 2001 at 00:22:17, Robert Hyatt wrote: > >>On January 14, 2001 at 00:05:08, Christophe Theron wrote: >> >>>On January 13, 2001 at 17:19:19, Robert Hyatt wrote: >>> >>>>On January 13, 2001 at 17:13:13, Gian-Carlo Pascutto wrote: >>>> >>>>>Hi all, >>>>> >>>>>I just added code to my program to handle fractional extensions >>>>>and recapture extensions. >>>>> >>>>>My problem now is: how do I test & tune these? I did what I >>>>>normally do and ran it through WAC. It did worse. Probably not >>>>>so surprising as they are nearly all rather simple tactical >>>>>positions, so extending more (on checks...not so much on >>>>>recaptures) is nearly always a win. >>>>> >>>>>Does anybody here have a testcase? Maybe a set of positions >>>>>where it _really_ matters how you do your extensions? >>>>> >>>>>If you added frac. extensions you your program, what made you >>>>>decide to do so? >>>>> >>>>>-- >>>>>GCP >>>> >>>> >>>>Do as I did. Make the extension amount something you can set via command. >>>>Then run a potload of tests. I ran WAC with all the extensions set to >>>>values between .5 and 1.0, in increments of .25. That is 3 cases for >>>>each extension and I varied 4 different extensions. 81 tests and you then >>>>look at which ones needed the fewest total nodes to solve _all_ the test >>>>positions... >>> >>> >>> >>> >>>So Crafty is cooked for WAC!? ;) >>> >>> >>> >>> Christophe >> >> >>:) >> >>actually not, as I used a lot of other positions as well (IE I used some of >>the "crafty goes deep" positions that were not tactical at all....) > > > >I am still using full ply extensions. > >I think I should try fractional extensions. Actually I did in the past. My 16 >bits version used fractional extensions (in 1/100th of ply), but I was also >doing much more extensions. I mean I had more reasons to do extensions. > >As for now, I prefer to be extremely "selective" in my extensions. There are a >lot of conditions to meet before Tiger triggers an extension. > > > > Christophe Fractional ply extensions give a chance for better control. IE you can say "OK, I want to extend 3 checks, then not extend 1, then extend the next three, but not the next... then you use a 3/4 ply extension... it is also useful for controlling the one-legal-reply extension since that is really a double extension on one ply and extending _two_ plies is potentially catastrophic.
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