def test_warn_if_transform_df_contains_categories_not_seen_in_fit(
df_enc, df_enc_rare):
# test case 3: when dataset to be transformed contains categories not present
# in training dataset
msg = "During the encoding, NaN values were introduced in the feature(s) var_A."
# check for error when rare_labels equals 'raise'
with pytest.warns(UserWarning) as record:
encoder = WoEEncoder(errors="ignore")
encoder.fit(df_enc[["var_A", "var_B"]], df_enc["target"])
encoder.transform(df_enc_rare[["var_A", "var_B"]])
# check that only one warning was raised
assert len(record) == 1
# check that the message matches
assert record[0].message.args[0] == msg
# check for error when rare_labels equals 'raise'
with pytest.raises(ValueError) as record:
encoder = WoEEncoder(errors="raise")
encoder.fit(df_enc[["var_A", "var_B"]], df_enc["target"])
encoder.transform(df_enc_rare[["var_A", "var_B"]])
# check that the error message matches
assert str(record.value) == msg
def test_warn_if_transform_df_contains_categories_not_seen_in_fit(
df_enc, df_enc_rare):
# test case 3: when dataset to be transformed contains categories not present
# in training dataset
encoder = WoEEncoder(variables=None)
with pytest.warns(UserWarning):
encoder.fit(df_enc[["var_A", "var_B"]], df_enc["target"])
encoder.transform(df_enc_rare[["var_A", "var_B"]])
def test_variables_cast_as_category(df_enc_category_dtypes):
df = df_enc_category_dtypes.copy()
encoder = WoEEncoder(variables=None)
encoder.fit(df[["var_A", "var_B"]], df["target"])
X = encoder.transform(df[["var_A", "var_B"]])
# transformed dataframe
transf_df = df.copy()
transf_df["var_A"] = [
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
]
transf_df["var_B"] = [
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
]
pd.testing.assert_frame_equal(X,
transf_df[["var_A", "var_B"]],
check_dtype=False)
assert X["var_A"].dtypes == float
def test_error_if_target_not_binary():
# test case 4: the target is not binary
encoder = WoEEncoder(variables=None)
with pytest.raises(ValueError):
df = {
"var_A": ["A"] * 6 + ["B"] * 10 + ["C"] * 4,
"var_B": ["A"] * 10 + ["B"] * 6 + ["C"] * 4,
"target":
[1, 1, 2, 2, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0],
}
df = pd.DataFrame(df)
encoder.fit(df[["var_A", "var_B"]], df["target"])
def test_error_if_denominator_probability_is_zero():
# test case 5: when the denominator probability is zero
encoder = WoEEncoder(variables=None)
with pytest.raises(ValueError):
df = {
"var_A": ["A"] * 6 + ["B"] * 10 + ["C"] * 4,
"var_B": ["A"] * 10 + ["B"] * 6 + ["C"] * 4,
"target":
[1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0],
}
df = pd.DataFrame(df)
encoder.fit(df[["var_A", "var_B"]], df["target"])
def test_error_target_is_not_passed(df_enc):
# test case 2: raises error if target is not passed
encoder = WoEEncoder(variables=None)
with pytest.raises(TypeError):
encoder.fit(df_enc)
def test_automatically_select_variables(df_enc):
# test case 1: automatically select variables, woe
encoder = WoEEncoder(variables=None)
encoder.fit(df_enc[["var_A", "var_B"]], df_enc["target"])
X = encoder.transform(df_enc[["var_A", "var_B"]])
# transformed dataframe
transf_df = df_enc.copy()
transf_df["var_A"] = [
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
]
transf_df["var_B"] = [
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
]
# init params
assert encoder.variables == ["var_A", "var_B"]
# fit params
assert encoder.encoder_dict_ == {
"var_A": {
"A": 0.15415067982725836,
"B": -0.5389965007326869,
"C": 0.8472978603872037,
},
"var_B": {
"A": -0.5389965007326869,
"B": 0.15415067982725836,
"C": 0.8472978603872037,
},
}
assert encoder.input_shape_ == (20, 2)
# transform params
pd.testing.assert_frame_equal(X, transf_df[["var_A", "var_B"]])
def test_error_if_df_contains_na_in_transform(df_enc, df_enc_na):
# test case 10: when dataset contains na, transform method}
encoder = WoEEncoder(variables=None)
with pytest.raises(ValueError):
encoder.fit(df_enc[["var_A", "var_B"]], df_enc["target"])
encoder.transform(df_enc_na)
def test_error_if_contains_na_in_fit(df_enc_na):
# test case 9: when dataset contains na, fit method
encoder = WoEEncoder(variables=None)
with pytest.raises(ValueError):
encoder.fit(df_enc_na[["var_A", "var_B"]], df_enc_na["target"])
def test_on_numerical_variables(df_enc_numeric):
# ignore_format=True
encoder = WoEEncoder(variables=None, ignore_format=True)
encoder.fit(df_enc_numeric[["var_A", "var_B"]], df_enc_numeric["target"])
X = encoder.transform(df_enc_numeric[["var_A", "var_B"]])
# transformed dataframe
transf_df = df_enc_numeric.copy()
transf_df["var_A"] = [
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
]
transf_df["var_B"] = [
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
-0.5389965007326869,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.15415067982725836,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
0.8472978603872037,
]
# init params
assert encoder.variables is None
# fit params
assert encoder.variables_ == ["var_A", "var_B"]
assert encoder.encoder_dict_ == {
"var_A": {
1: 0.15415067982725836,
2: -0.5389965007326869,
3: 0.8472978603872037,
},
"var_B": {
1: -0.5389965007326869,
2: 0.15415067982725836,
3: 0.8472978603872037,
},
}
assert encoder.n_features_in_ == 2
# transform params
pd.testing.assert_frame_equal(X, transf_df[["var_A", "var_B"]])