diff --git a/simulations/lib/util.py b/simulations/lib/util.py
index ef69931..59f1a1b 100644
--- a/simulations/lib/util.py
+++ b/simulations/lib/util.py
@@ -18,3 +18,21 @@ def rot_vector(phi1=0.12345):
             ])
 
     return np.cos(unit)
+
+def detect_edges(threshold, data, rising=True, falling=False):
+    """
+    Detect rising/falling edges in data, returning the indices
+    of the detected edges.
+
+    https://stackoverflow.com/a/50365462
+    """
+
+    mask = np.full(len(data), False)
+
+    if rising:
+        mask |= (data[:-1] < threshold) & (data[1:] > threshold)
+
+    if falling:
+        mask |= (data[:-1] > threshold) & (data[1:] < threshold)
+
+    return np.flatnonzero(mask)+1