Equalizer Iccf

[MichaelR]

First, I have to thank the incredible work of the Stockfish programmers for bringing this engine to a truly high level.
Reading criticisms of the new versions in solving chess tests, I wanted to create a personal variant in this direction, starting from Stockfish dev. 240307, calling it Equalizer 24.4
For now I have ONLY changed the following structure:

Code: Select all

Value Eval::evaluate(const Position& pos, int optimism) {
	
    assert(!pos.checkers());

    int v;
    int nnueComplexity;
    Value nnue;
    int simpleEval = simple_eval(pos, pos.side_to_move());
    int abs_simpleEval = std::abs(simpleEval);
	
	if (abs_simpleEval > 3000)
	{ 
	    ...
	}
	else if (abs_simpleEval > 2500)  
	{ 
	    ...
	}
	else if (abs_simpleEval > 2000)  
	{ 
	    ...
	}
	else if (abs_simpleEval > 1500)  
	{ 
	    ...
	}
	else if (abs_simpleEval > 1000)  
	{ 
	    ...
	}
	else if (abs_simpleEval > 500)  
	{ 
	    ...
	}
	else  
	{ 
	    ...
	}

    // Guarantee evaluation does not hit the tablebase range
    v = std::clamp(v, VALUE_TB_LOSS_IN_MAX_PLY + 1, VALUE_TB_WIN_IN_MAX_PLY - 1);
    return v;
}

By optimizing each sector, the resolution of chess tests is incredibly improved, significantly improved in fast times, less so in slow ones.

tc=1.0+0.01
Score of Equalizer_24.4 vs Stockfish_240307: 5307 - 4673 - 10020 [515.85] 20000
tc=10.0+0.1
Score of Equalizer_24.4 vs Stockfish_240307: 144 - 77 - 1779 [516.75] 2000

These days I started using it on PlayChess.
I want to point out that I have no credit for this engine, all credit should be given to the Stockfish programmers, I'm just equalizing the evaluate() module.

Message from moderator Elijah

I formatted your post correctly regarding the code.
However, I invite you to read the forum rules and respect them.
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