def test_nan(self):
"""
NaN substituted to 0.
"""
value = float("nan")
self.assertEqual(substitute_nan(value), 0.0)
def test_non_default_subst(self):
"""
NaN substitute to non default.
"""
value = float("nan")
self.assertEqual(substitute_nan(value, 99), 99)
def test_not_nan(self):
"""
Non-NaN returned unchanged.
"""
value = 1
self.assertEqual(substitute_nan(value), value)
