From 49773660fa36d2c00274a17f03b72a25b7862fa7 Mon Sep 17 00:00:00 2001
From: Keyan <keyan.zahedi@gmail.com>
Date: Wed, 3 Apr 2019 11:41:37 +0200
Subject: [PATCH] bug fix

---
 discrete/ProbabilityEstimator.go                | 9 +++++++++
 discrete/sparse/ConditionalMutualInformation.go | 6 +++---
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/discrete/ProbabilityEstimator.go b/discrete/ProbabilityEstimator.go
index 6cf68ce..d83265e 100644
--- a/discrete/ProbabilityEstimator.go
+++ b/discrete/ProbabilityEstimator.go
@@ -1,6 +1,8 @@
 package discrete
 
 import (
+	"math"
+
 	"github.com/kzahedi/goent/sm"
 )
 
@@ -137,8 +139,15 @@ func Empirical3DSparse(d [][]int) sm.SparseMatrix {
 	}
 
 	l := float64(rows)
+	var sum float64
 	for _, index := range p.Indices {
 		p.Mul(index, 1.0/l)
+		v, _ := p.Get(index)
+		sum += v
+	}
+
+	if math.Abs(sum-1.0) > 0.00001 {
+		panic("P does not sum up to one")
 	}
 
 	return p
diff --git a/discrete/sparse/ConditionalMutualInformation.go b/discrete/sparse/ConditionalMutualInformation.go
index a493c94..4657323 100644
--- a/discrete/sparse/ConditionalMutualInformation.go
+++ b/discrete/sparse/ConditionalMutualInformation.go
@@ -34,19 +34,19 @@ func ConditionalMutualInformation(pxyz sm.SparseMatrix, ln lnFunc) float64 {
 	for _, index := range pxyCz.Indices {
 		zi := sm.SparseMatrixIndex{index[2]}
 		v, _ := pz.Get(zi)
-		pxyCz.Mul(zi, 1.0/v)
+		pxyCz.Mul(index, 1.0/v)
 	}
 
 	for _, index := range pxCz.Indices {
 		zi := sm.SparseMatrixIndex{index[1]}
 		v, _ := pz.Get(zi)
-		pxCz.Mul(zi, 1.0/v)
+		pxCz.Mul(index, 1.0/v)
 	}
 
 	for _, index := range pyCz.Indices {
 		zi := sm.SparseMatrixIndex{index[1]}
 		v, _ := pz.Get(zi)
-		pyCz.Mul(zi, 1.0/v)
+		pyCz.Mul(index, 1.0/v)
 	}
 
 	r := 0.0