diff --git a/scripts/checkPulseData.py b/scripts/checkPulseData.py
index d2aceb4..60d4d24 100644
--- a/scripts/checkPulseData.py
+++ b/scripts/checkPulseData.py
@@ -63,6 +63,13 @@
     return (np.all(dx <= 0) or np.all(dx >= 0))
 
 
+def is_central(x):
+    if not len(x):
+        return False
+    dx = np.diff(x)
+    return (np.all(dx <= 0) or np.all(dx >= 0))
+
+
 def max_adc(x):
     return np.max(x)