From 45a2d08432942c1998786cbb28af9604f0cd6e18 Mon Sep 17 00:00:00 2001
From: evomarc <evomarc>
Date: Tue, 2 Sep 2003 05:49:37 +0000
Subject: [PATCH] Slightly modified the formula: the worst individual had
 "fitness" 0 in hte case of linear scaling with pressure=2. Now it has fitness
 1/[P(P-1)/2] Thanks to Gilles BAUDRILLARD (EADS)

---
 eo/src/eoRanking.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/eo/src/eoRanking.h b/eo/src/eoRanking.h
index 5b7421be..3918cc53 100644
--- a/eo/src/eoRanking.h
+++ b/eo/src/eoRanking.h
@@ -81,7 +81,7 @@ public:
 	  for (unsigned i=0; i<pSize; i++)
 	    {
 	      int which = lookfor(rank[i], _pop);
-	      value()[which] = alpha*(pSizeMinusOne-i)+beta;
+	      value()[which] = alpha*(pSize-i)+beta; // worst -> 1/[P(P-1)/2]
 	    }
 	}
       else				   // exponent != 1
@@ -91,7 +91,7 @@ public:
 	    {
 	      int which = lookfor(rank[i], _pop);
 	      // value in in [0,1]
-	      double tmp = ((double)(pSizeMinusOne-i))/pSizeMinusOne; 
+	      double tmp = ((double)(pSize-i))/pSize; 
 	      // to the exponent, and back to [m,M]
 	      value()[which] = gamma*pow(tmp, exponent)+beta;
 	    }