From: Marco Costalba <mcostalba@gmail.com>
Date: Wed, 1 Jan 2014 12:35:11 +0000 (+0100)
Subject: Further simplify move_importance()
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=a795187c50cdbe00d5364ce049d8673a04803c21

Further simplify move_importance()

Function move_importance() is already always
positive, so we don't need to add a constant
term to ensure it.

Becuase move_importance() is used to calculate
ratios of a linear combination (as explained in
previous patch), result is not affected. I have
also verified it directly.

No functional change.
---

diff --git a/src/timeman.cpp b/src/timeman.cpp
index fc2a327d..013d5f46 100644
--- a/src/timeman.cpp
+++ b/src/timeman.cpp
@@ -44,7 +44,7 @@ namespace {
 
   double move_importance(int ply) {
 
-    return 1 / pow((1 + exp((ply - xshift) / xscale)), skewfactor) + 1e-3; // Ensure non-zero
+    return 1 / pow((1 + exp((ply - xshift) / xscale)), skewfactor);
   }