Fix doc

Author: szhan

python/tests/test_beagle.py

@@ -119,13 +119,20 @@ def get_switch_prob(pos, h, ne=1e6):
     """
     Set switch probabilities at genotyped markers.
 
+    Note that in BEAGLE, the default value of `ne` is set to 1e6.
+    If `h` is small and `ne` is large, the switch probability is nearly 1.
+    In such cases, it may be desirable to set `ne` to a small value
+    to avoid switching between haplotypes all the time.
+
     :param numpy.ndarray pos: Site positions.
-    :param numpy.ndarray h: Number of reference haplotypes.
+    :param int h: Number of reference haplotypes.
     :param float ne: Effective population size.
     :return: Switch probabilities.
     :rtype: numpy.ndarray
     """
     assert pos[0] > 0, "Site positions are not 1-based."
+    assert isinstance(h, int), "Number of reference haplotypes is not an integer."
+    assert isinstance(ne, float), "Effective population size is not a float."
     # Get genetic distance between adjacent markers.
     cm = np.concatenate([[0], convert_to_genetic_map_position(pos)])
     gen_dist = cm[1:] - cm[:-1]