mcostalba / scoutfish

Chess Query Engine
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Proposed Material signature Rule. #48

Open rozim opened 6 years ago

rozim commented 6 years ago

This is a side effect of my query here: https://github.com/mcostalba/scoutfish/issues/47#issuecomment-348705395

I wanted to search for a certain pattern (2 Queens vs Q + RR) and it seemed that the existing rules couldn't do it.

I have done some ad hoc testing of this and it seems to work.

In retrospect possibly the existing "material" rule should be updated instead of a new rule being added.

For a proper pull I probably need to update the test code - but I've put this together so it's a kind of working proposal.

I don't use git(hub) much so please bear with me if I'm not following some convention.

thx, Dave

Obscure historical note: ages ago I was watching a post mortem at a chess tournament, maybe a game between 2 masters, and in their analysis there was a position with 2 queens vs Q+RR and GM Anthony Lein was watching, and they asked him how to evaluate it, and he said that QQ was usually much better - and ever since Larry Kaufmann wrote those articles about statistically evaluating material imbalances I've wanted to do it for this probably rare situation.