Author: Christophe Theron
Date: 17:59:43 01/16/01
Go up one level in this thread
On January 16, 2001 at 20:25:53, Bas Hamstra wrote:
>On January 15, 2001 at 21:33:02, Christophe Theron wrote:
>
>>On January 15, 2001 at 18:24:23, Bas Hamstra wrote:
>>
>>>On January 14, 2001 at 10:18:08, Robert Hyatt wrote:
>>>
>>>>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.
>>>
>>>They can also be very powerful, see Genius. It sees amazing things in 0 sec. So
>>>it can be done.
>>
>>
>>
>>Unfortunately this has nothing to do with fractional extensions.
>
>I was referring to extending more than 1 ply.
What Genius does is not achieved by extensions. That's what I meant.
Christophe
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