X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmisc.h;h=77b81d50fc00e02465413273e398a083f41de6c8;hb=154e7afed0fe9c6f45a2aee8ef6f38d44076cb19;hp=fe1143def0b35150eeedf51d3976baa46beb467e;hpb=5a871e174f22894837c2363b5c215854ee155113;p=stockfish diff --git a/src/misc.h b/src/misc.h index fe1143de..77b81d50 100644 --- a/src/misc.h +++ b/src/misc.h @@ -126,33 +126,6 @@ private: }; -/// sigmoid(t, x0, y0, C, P, Q) implements a sigmoid-like function using only integers, -/// with the following properties: -/// -/// - sigmoid is centered in (x0, y0) -/// - sigmoid has amplitude [-P/Q , P/Q] instead of [-1 , +1] -/// - limit is (y0 - P/Q) when t tends to -infinity -/// - limit is (y0 + P/Q) when t tends to +infinity -/// - the slope can be adjusted using C > 0, smaller C giving a steeper sigmoid -/// - the slope of the sigmoid when t = x0 is P/(Q*C) -/// - sigmoid is increasing with t when P > 0 and Q > 0 -/// - to get a decreasing sigmoid, change sign of P -/// - mean value of the sigmoid is y0 -/// -/// Use to draw the sigmoid - -inline int64_t sigmoid(int64_t t, int64_t x0, - int64_t y0, - int64_t C, - int64_t P, - int64_t Q) -{ - assert(C > 0); - assert(Q != 0); - return y0 + P * (t-x0) / (Q * (std::abs(t-x0) + C)) ; -} - - /// xorshift64star Pseudo-Random Number Generator /// This class is based on original code written and dedicated /// to the public domain by Sebastiano Vigna (2014).