diff --git a/modules/util/util.py b/modules/util/util.py
index 5831c5ba10b7fe313bd763f78d1efc1515db735c..872ed3d7e3ae5243c2791969c22368fa10d379aa 100644
--- a/modules/util/util.py
+++ b/modules/util/util.py
@@ -291,7 +291,8 @@ def minimize_quadratic(xa, xb, xc, ya, yb, yc):
     return x_m
 
 
-# Return index of nda closest to value. nda must be 1d
+# Return index of nda closest to value. nda (numpy.ndarray) must be 1d. If multiple occurrences should arise,
+# the first is returned according to NumPy's argmin/max function.
 def value_to_index(nda, value):
     diff = np.abs(nda - value)
     idx = np.argmin(diff)