Computer Chess Club Archives


Search

Terms

Messages

Subject: Question on Singular Extension

Author: William Bryant

Date: 06:35:09 06/23/99


As I understand the use of Singular extensions,
     when, after generating all the _legal_ moves, there is only one move to be
     made by the side on move, extend 1 ply.

Since you only extend a maximum of 1 ply at any node, if the King is in check,
     or any other extensions are also triggered you would be extending anyway
     and this only extends this branch of the tree when it is the only
     condition extending the search.

To generate legal moves, you must check each move to see if it places the King
     in danger of being captured, a procedure that I do at present in my
     MakeMove() function.  The difference being, that it takes more time to
     check for legality when generating the moves than it does in MakeMove()
     because cutoffs keep you from making and unmaking all the moves.

Now my question, is the extra time it takes to generate legal vs. pseudolegal
     moves made up in the search by the singular extension during those
     positions when nothing else would have triggered an extension in the
     search anyway?

Am I missing something?

Thank you.

William
wbryant@ix.netcom.com



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.