From f3a6eb0960321415fba34627e2740bdd7d3caebc Mon Sep 17 00:00:00 2001
From: Will Charczuk <will.charczuk@gmail.com>
Date: Mon, 18 Jul 2016 17:02:14 -0700
Subject: [PATCH] fixing sigma calc on empty period.

---
 ema_series.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ema_series.go b/ema_series.go
index fd5eda7..cd6ce13 100644
--- a/ema_series.go
+++ b/ema_series.go
@@ -45,7 +45,7 @@ func (ema EMASeries) Len() int {
 
 // GetSigma returns the smoothing factor for the serise.
 func (ema EMASeries) GetSigma() float64 {
-	return 2.0 / (float64(ema.Period) + 1)
+	return 2.0 / (float64(ema.GetPeriod()) + 1)
 }
 
 // GetValue gets a value at a given index.