merged NumericalTransformer

Author: RJ Agrawal

tests/test_transformers.py

@@ -0,0 +1,47 @@
+import tempfile
+import pytest
+import numpy as np
+from pandas import DataFrame
+import joblib
+
+from sklearn_pandas import DataFrameMapper
+from sklearn_pandas.transformers import NumericalTransformer
+
+
+@pytest.fixture
+def simple_dataset():
+    return DataFrame({
+        'feat1': [1, 2, 1, 3, 1],
+        'feat2': [1, 2, 2, 2, 3],
+        'feat3': [1, 2, 3, 4, 5],
+    })
+
+
+def test_common_numerical_transformer(simple_dataset):
+    """
+    Test log transformation
+    """
+    transfomer = DataFrameMapper([
+        ('feat1', NumericalTransformer('log'))
+    ], df_out=True)
+    df = simple_dataset
+    outDF = transfomer.fit_transform(df)
+    assert list(outDF.columns) == ['feat1']
+    assert np.array_equal(df['feat1'].apply(np.log).values, outDF.feat1.values)
+
+
+def test_numerical_transformer_serialization(simple_dataset):
+    """
+    Test if you can serialize transformer
+    """
+    transfomer = DataFrameMapper([
+        ('feat1', NumericalTransformer('log'))
+    ])
+
+    df = simple_dataset
+    transfomer.fit(df)
+    f = tempfile.NamedTemporaryFile(delete=True)
+    joblib.dump(transfomer, f.name)
+    transfomer2 = joblib.load(f.name)
+    np.array_equal(transfomer.transform(df), transfomer2.transform(df))
+    f.close()