diff --git a/README.md b/README.md
index 14a9958..6a6df75 100644
--- a/README.md
+++ b/README.md
@@ -36,7 +36,7 @@ Tested on TensorFlow version 0.11.0, 1.1.0 and 1.3.0 and Python 2.7 and 3.6.
 ## Usage
 
 ```
-python readLogs.py <output-folder> <output-path-to-csv> <summaries>
+python readLogs.py <input-path-to-logfile> <output-folder> <summaries>
 
 Inputs:
    <input-path-to-logfile>  - Path to TensorFlow logfile.
diff --git a/exportTensorFlowLog.py b/exportTensorFlowLog.py
index 436f269..d53d431 100644
--- a/exportTensorFlowLog.py
+++ b/exportTensorFlowLog.py
@@ -172,8 +172,12 @@ def exitWithUsage():
 				data = [v.wall_time, v.step];
 				for s in scalarTags:
 					scalarTag = ea.Scalars(s);
-					S = scalarTag[i];
-					data.append(S.value);
+					if i < len(scalarTag):
+						S = scalarTag[i];
+						data.append(S.value);
+					else:
+						print("ScalarTag {} is too short - writing NaN".format(s))
+						data.append(math.nan)
 				logWriter.writerow(data);
 
 print(' ');