From 108ab9402354df77fc508300944ad8c3a5d4ce49 Mon Sep 17 00:00:00 2001
From: Vadim Pisarevsky <no@email>
Date: Sun, 12 Dec 2010 22:45:31 +0000
Subject: [PATCH] improved naive bayes robustness in the case of singular data

---
 modules/ml/src/nbayes.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/ml/src/nbayes.cpp b/modules/ml/src/nbayes.cpp
index 5b636baca..483cc01e8 100644
--- a/modules/ml/src/nbayes.cpp
+++ b/modules/ml/src/nbayes.cpp
@@ -259,7 +259,7 @@ bool CvNormalBayesClassifier::train( const CvMat* _train_data, const CvMat* _res
             det *= w->data.db[j];
 
         CV_CALL( cvDiv( NULL, w, w ));
-        c->data.db[cls] = log( det );
+        c->data.db[cls] = det > 0 ? log(det) : -700;
     }
 
     result = true;