def test_reverse_transform_int(self):
"""Test the ``GreaterThan.reverse_transform`` method for dtype int.
The ``GreaterThan.reverse_transform`` method is expected to:
- apply an exponential to the input
- subtract 1
- add the low column
- convert the output to integers
Input:
- Table with a high column that contains the constant np.log(4).
Output:
- Same table with the high column replaced by the low one + 3, as int.
"""
# Setup
instance = GreaterThan(low='a', high='b', strict=True)
instance._dtype = pd.Series(
[1]).dtype # exact dtype (32 or 64) depends on OS
# Run
transformed = pd.DataFrame({
'a': [1, 2, 3],
'b': [np.log(4)] * 3,
'c': [7, 8, 9]
})
out = instance.reverse_transform(transformed)
# Assert
expected_out = pd.DataFrame({
'a': [1, 2, 3],
'b': [4, 5, 6],
'c': [7, 8, 9],
})
pd.testing.assert_frame_equal(out, expected_out)
def test_reverse_transform_float(self):
"""Test the ``GreaterThan.reverse_transform`` method for dtype float.
The ``GreaterThan.reverse_transform`` method is expected to:
- apply an exponential to the input
- subtract 1
- add the low column
- convert the output to float values
Input:
- Table with a high column that contains the constant np.log(4).
Output:
- Same table with the high column replaced by the low one + 3, as float values.
"""
# Setup
instance = GreaterThan(low='a', high='b', strict=True)
instance._dtype = np.dtype('float')
# Run
transformed = pd.DataFrame({
'a': [1.1, 2.2, 3.3],
'b': [np.log(4)] * 3,
'c': [7, 8, 9]
})
out = instance.reverse_transform(transformed)
# Assert
expected_out = pd.DataFrame({
'a': [1.1, 2.2, 3.3],
'b': [4.1, 5.2, 6.3],
'c': [7, 8, 9],
})
pd.testing.assert_frame_equal(out, expected_out)
def test_reverse_transform(self):
"""Test the ``GreaterThan.reverse_transform`` method.
The ``GreaterThan.reverse_transform`` method is expected to:
- Return the original table data.
Input:
- Table data transformed (pandas.DataFrame)
Output:
- Table data (pandas.DataFrame)
Side effects:
- Since ``reverse_transform`` uses the class variable ``_dtype``, the ``fit`` method
must be called as well.
"""
# Setup
table_data = pd.DataFrame({
'a': [1, 2, 3],
'b': [4, 5, 6],
'c': [7, 8, 9]
})
instance = GreaterThan(low='a', high='b', strict=True)
instance.fit(table_data)
# Run
out = instance.reverse_transform(table_data)
# Assert
expected_out = pd.DataFrame({
'a': [1, 2, 3],
'b': [55, 149, 405],
'c': [7, 8, 9],
})
pd.testing.assert_frame_equal(out, expected_out)