add description to test and fix whitespace for code style

Ben Lawson · Ben Lawson · commit 2edb84c67b53 · 2018-10-01T11:10:35.000-04:00
diff --git a/sklearn/tests/test_impute.py b/sklearn/tests/test_impute.py
@@ -593,6 +593,9 @@ def test_iterative_imputer_clip():
 
 
 def test_iterative_imputer_normal_posterior():
+    #  test that the values that are imputed using `sample_posterior=True`
+    #  with boundaries (`min_value` and `max_value` are not None) are drawn
+    #  from a distribution that looks gaussian via the Kolmogorov–Smirnov test
     rng = np.random.RandomState(0)
 
     X = rng.random_sample((5, 5))
@@ -607,7 +610,7 @@ def test_iterative_imputer_normal_posterior():
     # generate multiple imputations for the single missing value
     imputations = np.array([imputer.transform(X)[0][0] for _ in range(1000)])
     mu, sigma = imputations.mean(), imputations.std()
-    ks_statistic, p_value = kstest((imputations-mu)/sigma, 'norm')
+    ks_statistic, p_value = kstest((imputations - mu) / sigma, 'norm')
     # we want to fail to reject null hypothesis
     # null hypothesis: distributions are the same
     assert ks_statistic < 0.15 or p_value > 0.1, \
