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Subject: Re: Buggy check extensions, back to square one =(.

Author: Albert Bertilsson

Date: 13:29:47 03/22/03

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On March 21, 2003 at 19:01:15, Anthony Cozzie wrote:

>Debugging Suggestion (from the desk of Vincent Diepeveen, actually):
>
>Make a header file for sharper with code that looks like so:
>
>#ifdef _DEBUG_LOGGING_ENABLED_
>#define print_ab_entry printf("ndid: %d new subcall of alpha-beta, windows =
>etc");
>#endif
>#else
>#define print_ab_entry
>#endif
>
>This way my source still looks good without thousands of #ifdefs in the code,
>and I can turn on debugging and log everything zappa does: every hash probe,
>every recursive call, etc.  You can use grep to look at the file, e.g.:
>
>grep 000000001 zappa_debug_log
>
>000000001: calling PVS, childid = 000000001, move= Nd4, A=800, B=900, D=3,
>check=1
>000000001: PVS returns, score=835
>000000001: calling PVS, childid = 000000003, move= Ne3, A=835, B=900, D=2,
>check=0
>000000001: PVS returns, score=625
>
>Then, suppose there is an error with the evaluation of Ne3, I type grep
>000000003 zappa_debug_log and I can rapidly zero in on the problem.
>
>One of the problems with alpha-beta is that it will 'hide' errors from you.
>Your program almost certainly has bugs in the hashing (it took me *8 months* to
>iron out everything in zappa and I still don't completely trust the hash table),
>and probably other bugs.
>
>anthony
Thanx for the tip, I'll have a look at this, I'm still a novice so I guess it
will take me some time to understand what's causing my problems. And I'll
definetly have a close look at hash keys although I feel quite confident in them
(that confidence might be the real trouble!).

/Regards Albert



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