def test_otago_example(self):
dataset = self.create_otago_dataset()
transformed = self.get_transformed_otago_data()
principal_components = pca.pca(dataset, 2)
assert_that(principal_components, equals_dataset(transformed,
places=2))
def test_get_weights(self):
dataset = self.create_otago_dataset()
reduced = pca.pca(dataset, 2)
# Note: this is mostly a regression test, these expected values were
# obtained by running the code.
assert_that(
pd.DataFrame(reduced.get_weights()),
equals_dataframe(
[[-0.6778734, -0.73517866], [-0.73517866, 0.6778734]],
places=3))
def test_get_first_component_feature_weights(self):
dataset = self.create_otago_dataset()
reduced = pca.pca(dataset, 2)
# see note in test_get_weights
impacts = reduced.get_first_component_impacts()
assert_that(impacts,
equals_series({
"x": 0.6778734,
"y": 0.73517866
}, places=3))
# verify order
assert_that(impacts.index, contains("y", "x"))
def test_reduced_dataset_has_row_indices(self):
dataset = DataSet(
pd.DataFrame([[1, 2], [3, 4], [5, 6]], index=["Cat", "Dog",
"Rat"]))
reduced = pca.pca(dataset, 2)
assert_that(reduced.get_sample_ids(), contains("Cat", "Dog", "Rat"))
