X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fuci.cpp;fp=src%2Fuci.cpp;h=b3738a4a76b8705a668db9bb38bcf879a03ed0d8;hp=d5ffa2283197eaa73901620d971407106bb969d7;hb=dc4983327df7bf30eafd049aa777d0636ee4c0ed;hpb=e47b74457ef12ff28ced317fef942cfad18b18a0 diff --git a/src/uci.cpp b/src/uci.cpp index d5ffa228..b3738a4a 100644 --- a/src/uci.cpp +++ b/src/uci.cpp @@ -207,13 +207,13 @@ namespace { // Coefficients of a 3rd order polynomial fit based on fishtest data // for two parameters needed to transform eval to the argument of a // logistic function. - double as[] = {-8.24404295, 64.23892342, -95.73056462, 153.86478679}; - double bs[] = {-3.37154371, 28.44489198, -56.67657741, 72.05858751}; + double as[] = {-3.68389304, 30.07065921, -60.52878723, 149.53378557}; + double bs[] = {-2.0181857, 15.85685038, -29.83452023, 47.59078827}; double a = (((as[0] * m + as[1]) * m + as[2]) * m) + as[3]; double b = (((bs[0] * m + bs[1]) * m + bs[2]) * m) + bs[3]; // Transform eval to centipawns with limited range - double x = std::clamp(double(100 * v) / PawnValueEg, -1000.0, 1000.0); + double x = std::clamp(double(100 * v) / PawnValueEg, -2000.0, 2000.0); // Return win rate in per mille (rounded to nearest) return int(0.5 + 1000 / (1 + std::exp((a - x) / b)));