Files
stree/stree/tests/Stree_test.py
2020-06-26 11:22:45 +02:00

417 lines
16 KiB
Python

import os
import unittest
import warnings
import numpy as np
from sklearn.datasets import load_iris, load_wine
from sklearn.exceptions import ConvergenceWarning
from stree import Stree, Snode
from .utils import load_dataset
class Stree_test(unittest.TestCase):
def __init__(self, *args, **kwargs):
self._random_state = 1
self._kernels = ["linear", "rbf", "poly"]
super().__init__(*args, **kwargs)
@classmethod
def setUp(cls):
os.environ["TESTING"] = "1"
def _check_tree(self, node: Snode):
"""Check recursively that the nodes that are not leaves have the
correct number of labels and its sons have the right number of elements
in their dataset
Arguments:
node {Snode} -- node to check
"""
if node.is_leaf():
return
y_prediction = node._clf.predict(node._X)
y_down = node.get_down()._y
y_up = node.get_up()._y
# Is a correct partition in terms of cadinality?
# i.e. The partition algorithm didn't forget any sample
self.assertEqual(node._y.shape[0], y_down.shape[0] + y_up.shape[0])
unique_y, count_y = np.unique(node._y, return_counts=True)
_, count_d = np.unique(y_down, return_counts=True)
_, count_u = np.unique(y_up, return_counts=True)
#
for i in unique_y:
number_down = count_d[i]
try:
number_up = count_u[i]
except IndexError:
number_up = 0
self.assertEqual(count_y[i], number_down + number_up)
# Is the partition made the same as the prediction?
# as the node is not a leaf...
_, count_yp = np.unique(y_prediction, return_counts=True)
self.assertEqual(count_yp[0], y_up.shape[0])
self.assertEqual(count_yp[1], y_down.shape[0])
self._check_tree(node.get_down())
self._check_tree(node.get_up())
def test_build_tree(self):
"""Check if the tree is built the same way as predictions of models
"""
warnings.filterwarnings("ignore")
for kernel in self._kernels:
clf = Stree(kernel=kernel, random_state=self._random_state)
clf.fit(*load_dataset(self._random_state))
self._check_tree(clf.tree_)
def test_single_prediction(self):
X, y = load_dataset(self._random_state)
for kernel in self._kernels:
clf = Stree(kernel=kernel, random_state=self._random_state)
yp = clf.fit(X, y).predict((X[0, :].reshape(-1, X.shape[1])))
self.assertEqual(yp[0], y[0])
def test_multiple_prediction(self):
# First 27 elements the predictions are the same as the truth
num = 27
X, y = load_dataset(self._random_state)
for kernel in self._kernels:
clf = Stree(kernel=kernel, random_state=self._random_state)
yp = clf.fit(X, y).predict(X[:num, :])
self.assertListEqual(y[:num].tolist(), yp.tolist())
def test_single_vs_multiple_prediction(self):
"""Check if predicting sample by sample gives the same result as
predicting all samples at once
"""
X, y = load_dataset(self._random_state)
for kernel in self._kernels:
clf = Stree(kernel=kernel, random_state=self._random_state)
clf.fit(X, y)
# Compute prediction line by line
yp_line = np.array([], dtype=int)
for xp in X:
yp_line = np.append(
yp_line, clf.predict(xp.reshape(-1, X.shape[1]))
)
# Compute prediction at once
yp_once = clf.predict(X)
self.assertListEqual(yp_line.tolist(), yp_once.tolist())
def test_iterator_and_str(self):
"""Check preorder iterator
"""
expected = [
"root feaures=(0, 1, 2) impurity=0.5000",
"root - Down feaures=(0, 1, 2) impurity=0.0671",
"root - Down - Down, <cgaf> - Leaf class=1 belief= 0.975989 "
"impurity=0.0469 counts=(array([0, 1]), array([ 17, 691]))",
"root - Down - Up feaures=(0, 1, 2) impurity=0.3967",
"root - Down - Up - Down, <cgaf> - Leaf class=1 belief= 0.750000 "
"impurity=0.3750 counts=(array([0, 1]), array([1, 3]))",
"root - Down - Up - Up, <pure> - Leaf class=0 belief= 1.000000 "
"impurity=0.0000 counts=(array([0]), array([7]))",
"root - Up, <cgaf> - Leaf class=0 belief= 0.928297 impurity=0.1331"
" counts=(array([0, 1]), array([725, 56]))",
]
computed = []
expected_string = ""
clf = Stree(kernel="linear", random_state=self._random_state)
clf.fit(*load_dataset(self._random_state))
for node in clf:
computed.append(str(node))
expected_string += str(node) + "\n"
self.assertListEqual(expected, computed)
self.assertEqual(expected_string, str(clf))
@staticmethod
def test_is_a_sklearn_classifier():
warnings.filterwarnings("ignore", category=ConvergenceWarning)
warnings.filterwarnings("ignore", category=RuntimeWarning)
from sklearn.utils.estimator_checks import check_estimator
check_estimator(Stree())
def test_exception_if_C_is_negative(self):
tclf = Stree(C=-1)
with self.assertRaises(ValueError):
tclf.fit(*load_dataset(self._random_state))
def test_exception_if_bogus_split_criteria(self):
tclf = Stree(split_criteria="duck")
with self.assertRaises(ValueError):
tclf.fit(*load_dataset(self._random_state))
def test_check_max_depth_is_positive_or_None(self):
tcl = Stree()
self.assertIsNone(tcl.max_depth)
tcl = Stree(max_depth=1)
self.assertGreaterEqual(1, tcl.max_depth)
with self.assertRaises(ValueError):
tcl = Stree(max_depth=-1)
tcl.fit(*load_dataset(self._random_state))
def test_check_max_depth(self):
depths = (3, 4)
for depth in depths:
tcl = Stree(random_state=self._random_state, max_depth=depth)
tcl.fit(*load_dataset(self._random_state))
self.assertEqual(depth, tcl.depth_)
def test_unfitted_tree_is_iterable(self):
tcl = Stree()
self.assertEqual(0, len(list(tcl)))
def test_min_samples_split(self):
dataset = [[1], [2], [3]], [1, 1, 0]
tcl_split = Stree(min_samples_split=3).fit(*dataset)
self.assertIsNotNone(tcl_split.tree_.get_down())
self.assertIsNotNone(tcl_split.tree_.get_up())
tcl_nosplit = Stree(min_samples_split=4).fit(*dataset)
self.assertIsNone(tcl_nosplit.tree_.get_down())
self.assertIsNone(tcl_nosplit.tree_.get_up())
def test_simple_muticlass_dataset(self):
for kernel in self._kernels:
clf = Stree(
kernel=kernel,
split_criteria="max_samples",
random_state=self._random_state,
)
px = [[1, 2], [5, 6], [9, 10]]
py = [0, 1, 2]
clf.fit(px, py)
self.assertEqual(1.0, clf.score(px, py))
self.assertListEqual(py, clf.predict(px).tolist())
self.assertListEqual(py, clf.classes_.tolist())
def test_muticlass_dataset(self):
datasets = {
"Synt": load_dataset(random_state=self._random_state, n_classes=3),
"Iris": load_iris(return_X_y=True),
}
outcomes = {
"Synt": {
"max_samples linear": 0.9533333333333334,
"max_samples rbf": 0.836,
"max_samples poly": 0.9473333333333334,
"min_distance linear": 0.9533333333333334,
"min_distance rbf": 0.836,
"min_distance poly": 0.9473333333333334,
"max_distance linear": 0.9533333333333334,
"max_distance rbf": 0.836,
"max_distance poly": 0.9473333333333334,
},
"Iris": {
"max_samples linear": 0.98,
"max_samples rbf": 1.0,
"max_samples poly": 1.0,
"min_distance linear": 0.98,
"min_distance rbf": 1.0,
"min_distance poly": 1.0,
"max_distance linear": 0.98,
"max_distance rbf": 1.0,
"max_distance poly": 1.0,
},
}
for name, dataset in datasets.items():
px, py = dataset
for criteria in ["max_samples", "min_distance", "max_distance"]:
for kernel in self._kernels:
clf = Stree(
C=1e4,
max_iter=1e4,
kernel=kernel,
random_state=self._random_state,
)
clf.fit(px, py)
outcome = outcomes[name][f"{criteria} {kernel}"]
self.assertAlmostEqual(outcome, clf.score(px, py))
def test_max_features(self):
n_features = 16
expected_values = [
("auto", 4),
("log2", 4),
("sqrt", 4),
(0.5, 8),
(3, 3),
(None, 16),
]
clf = Stree()
clf.n_features_ = n_features
for max_features, expected in expected_values:
clf.set_params(**dict(max_features=max_features))
computed = clf._initialize_max_features()
self.assertEqual(expected, computed)
# Check bogus max_features
values = ["duck", -0.1, 0.0]
for max_features in values:
clf.set_params(**dict(max_features=max_features))
with self.assertRaises(ValueError):
_ = clf._initialize_max_features()
def test_get_subspaces(self):
dataset = np.random.random((10, 16))
y = np.random.randint(0, 2, 10)
expected_values = [
("auto", 4),
("log2", 4),
("sqrt", 4),
(0.5, 8),
(3, 3),
(None, 16),
]
clf = Stree()
for max_features, expected in expected_values:
clf.set_params(**dict(max_features=max_features))
clf.fit(dataset, y)
computed, indices = clf.splitter_.get_subspace(
dataset, y, clf.max_features_
)
self.assertListEqual(
dataset[:, indices].tolist(), computed.tolist()
)
self.assertEqual(expected, len(indices))
def test_bogus_criterion(self):
clf = Stree(criterion="duck")
with self.assertRaises(ValueError):
clf.fit(*load_dataset())
def test_predict_feature_dimensions(self):
X = np.random.rand(10, 5)
y = np.random.randint(0, 2, 10)
clf = Stree()
clf.fit(X, y)
with self.assertRaises(ValueError):
clf.predict(X[:, :3])
# Tests of score
def test_score_binary(self):
X, y = load_dataset(self._random_state)
accuracies = [
0.9506666666666667,
0.9606666666666667,
0.9433333333333334,
]
for kernel, accuracy_expected in zip(self._kernels, accuracies):
clf = Stree(random_state=self._random_state, kernel=kernel,)
clf.fit(X, y)
accuracy_score = clf.score(X, y)
yp = clf.predict(X)
accuracy_computed = np.mean(yp == y)
self.assertEqual(accuracy_score, accuracy_computed)
self.assertAlmostEqual(accuracy_expected, accuracy_score)
def test_score_max_features(self):
X, y = load_dataset(self._random_state)
clf = Stree(random_state=self._random_state, max_features=2)
clf.fit(X, y)
self.assertAlmostEqual(0.9426666666666667, clf.score(X, y))
def test_score_multi_class(self):
warnings.filterwarnings("ignore")
accuracies = [
0.8258427, # Wine linear min_distance
0.6741573, # Wine linear max_distance
0.8314607, # Wine linear max_samples
0.6629213, # Wine rbf min_distance
1.0000000, # Wine rbf max_distance
0.4044944, # Wine rbf max_samples
0.9157303, # Wine poly min_distance
1.0000000, # Wine poly max_distance
0.7640449, # Wine poly max_samples
0.9933333, # Iris linear min_distance
0.9666667, # Iris linear max_distance
0.9666667, # Iris linear max_samples
0.9800000, # Iris rbf min_distance
0.9800000, # Iris rbf max_distance
0.9800000, # Iris rbf max_samples
1.0000000, # Iris poly min_distance
1.0000000, # Iris poly max_distance
1.0000000, # Iris poly max_samples
0.8993333, # Synthetic linear min_distance
0.6533333, # Synthetic linear max_distance
0.9313333, # Synthetic linear max_samples
0.8320000, # Synthetic rbf min_distance
0.6660000, # Synthetic rbf max_distance
0.8320000, # Synthetic rbf max_samples
0.6066667, # Synthetic poly min_distance
0.6840000, # Synthetic poly max_distance
0.6340000, # Synthetic poly max_samples
]
datasets = [
("Wine", load_wine(return_X_y=True)),
("Iris", load_iris(return_X_y=True)),
(
"Synthetic",
load_dataset(self._random_state, n_classes=3, n_features=5),
),
]
for dataset_name, dataset in datasets:
X, y = dataset
for kernel in self._kernels:
for criteria in [
"min_distance",
"max_distance",
"max_samples",
]:
clf = Stree(
C=17,
random_state=self._random_state,
kernel=kernel,
split_criteria=criteria,
degree=5,
gamma="auto",
)
clf.fit(X, y)
accuracy_score = clf.score(X, y)
yp = clf.predict(X)
accuracy_computed = np.mean(yp == y)
# print(
# "{:.7f}, # {:7} {:5} {}".format(
# accuracy_score, dataset_name, kernel, criteria
# )
# )
accuracy_expected = accuracies.pop(0)
self.assertEqual(accuracy_score, accuracy_computed)
self.assertAlmostEqual(accuracy_expected, accuracy_score)
def test_bogus_splitter_parameter(self):
clf = Stree(splitter="duck")
with self.assertRaises(ValueError):
clf.fit(*load_dataset())
def test_weights_removing_class(self):
# This patch solves an stderr message from sklearn svm lib
# "WARNING: class label x specified in weight is not found"
X = np.array(
[
[0.1, 0.1],
[0.1, 0.2],
[0.2, 0.1],
[5, 6],
[8, 9],
[6, 7],
[0.2, 0.2],
]
)
y = np.array([0, 0, 0, 1, 1, 1, 0])
epsilon = 1e-5
weights = [1, 1, 1, 0, 0, 0, 1]
weights = np.array(weights, dtype="float64")
weights_epsilon = [x + epsilon for x in weights]
weights_no_zero = np.array([1, 1, 1, 0, 0, 2, 1])
original = weights_no_zero.copy()
clf = Stree()
clf.fit(X, y)
node = clf.train(X, y, weights, 1, "test",)
# if a class is lost with zero weights the patch adds epsilon
self.assertListEqual(weights.tolist(), weights_epsilon)
self.assertListEqual(node._sample_weight.tolist(), weights_epsilon)
# zero weights are ok when they don't erase a class
_ = clf.train(X, y, weights_no_zero, 1, "test")
self.assertListEqual(weights_no_zero.tolist(), original.tolist())