diff --git a/python/tests/beagle_numba.py b/python/tests/beagle_numba.py
index 8a6cdcc5d2..8ab5a732f0 100644
--- a/python/tests/beagle_numba.py
+++ b/python/tests/beagle_numba.py
@@ -67,7 +67,10 @@ def convert_to_genetic_map_positions(pos, genetic_map=None):
         fb = genetic_map.gen_pos[
             left_idx[i]
         ]  # Genetic map position at right of marker i.
-        est_gen_pos[i] = fa + (pos[i] - a) / (b - a) * (fa - fb)
+        assert pos[i] > a, "Query position not greater than left-bound position."
+        assert b > a, "Physical positions not in ascending order."
+        assert fb > fa, "Genetic map positions not in ascending order."
+        est_gen_pos[i] = fa + (pos[i] - a) / (b - a) * (fb - fa)
     return est_gen_pos