Revert "[SPARK-12006][ML][PYTHON] Fix GMM failure if initialModel is …

…not None"

This reverts commit fcd013c.

Author: Yin Huai <yhuai@databricks.com>

Closes #10632 from yhuai/pythonStyle.

python/pyspark/mllib/clustering.py

@@ -346,7 +346,7 @@ def train(cls, rdd, k, convergenceTol=1e-3, maxIterations=100, seed=None, initia
             if initialModel.k != k:
                 raise Exception("Mismatched cluster count, initialModel.k = %s, however k = %s"
                                 % (initialModel.k, k))
-            initialModelWeights = list(initialModel.weights)
+            initialModelWeights = initialModel.weights
             initialModelMu = [initialModel.gaussians[i].mu for i in range(initialModel.k)]
             initialModelSigma = [initialModel.gaussians[i].sigma for i in range(initialModel.k)]
         java_model = callMLlibFunc("trainGaussianMixtureModel", rdd.map(_convert_to_vector),

python/pyspark/mllib/tests.py

@@ -475,18 +475,6 @@ def test_gmm_deterministic(self):
         for c1, c2 in zip(clusters1.weights, clusters2.weights):
             self.assertEqual(round(c1, 7), round(c2, 7))
 
-    def test_gmm_with_initial_model(self):
-        from pyspark.mllib.clustering import GaussianMixture
-        data = self.sc.parallelize([
-            (-10, -5), (-9, -4), (10, 5), (9, 4)
-        ])
-
-        gmm1 = GaussianMixture.train(data, 2, convergenceTol=0.001,
-                                     maxIterations=10, seed=63)
-        gmm2 = GaussianMixture.train(data, 2, convergenceTol=0.001,
-                                     maxIterations=10, seed=63, initialModel=gmm1)
-        self.assertAlmostEqual((gmm1.weights - gmm2.weights).sum(), 0.0)      
-
     def test_classification(self):
         from pyspark.mllib.classification import LogisticRegressionWithSGD, SVMWithSGD, NaiveBayes
         from pyspark.mllib.tree import DecisionTree, DecisionTreeModel, RandomForest,\