Files
stree/stree/tests/Splitter_test.py
Ricardo Montañana Gómez 36816074ff Combinatorial explosion (#19)
* Remove itertools combinations from subspaces

* Generates 5 random subspaces at most
2021-01-10 13:32:22 +01:00

225 lines
8.3 KiB
Python

import os
import unittest
import random
import numpy as np
from sklearn.svm import SVC
from sklearn.datasets import load_wine, load_iris
from stree import Splitter
class Splitter_test(unittest.TestCase):
def __init__(self, *args, **kwargs):
self._random_state = 1
super().__init__(*args, **kwargs)
@staticmethod
def build(
clf=SVC,
min_samples_split=0,
splitter_type="random",
criterion="gini",
criteria="max_samples",
random_state=None,
):
return Splitter(
clf=clf(random_state=random_state, kernel="rbf"),
min_samples_split=min_samples_split,
splitter_type=splitter_type,
criterion=criterion,
criteria=criteria,
random_state=random_state,
)
@classmethod
def setUp(cls):
os.environ["TESTING"] = "1"
def test_init(self):
with self.assertRaises(ValueError):
self.build(criterion="duck")
with self.assertRaises(ValueError):
self.build(splitter_type="duck")
with self.assertRaises(ValueError):
self.build(criteria="duck")
with self.assertRaises(ValueError):
_ = Splitter(clf=None)
for splitter_type in ["best", "random"]:
for criterion in ["gini", "entropy"]:
for criteria in ["max_samples", "impurity"]:
tcl = self.build(
splitter_type=splitter_type,
criterion=criterion,
criteria=criteria,
)
self.assertEqual(splitter_type, tcl._splitter_type)
self.assertEqual(criterion, tcl._criterion)
self.assertEqual(criteria, tcl._criteria)
def test_gini(self):
expected_values = [
([0, 1, 1, 1, 1, 1, 0, 0, 0, 1], 0.48),
([0, 1, 1, 2, 2, 3, 4, 5, 3, 2, 1, 1], 0.7777777777777778),
([0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 2, 2, 2], 0.520408163265306),
([0, 0, 1, 1, 1, 1, 0, 0], 0.5),
([0, 0, 1, 1, 2, 2, 3, 3], 0.75),
([0, 0, 1, 1, 1, 1, 1, 1], 0.375),
([0], 0),
([1, 1, 1, 1], 0),
]
for labels, expected in expected_values:
self.assertAlmostEqual(expected, Splitter._gini(labels))
tcl = self.build(criterion="gini")
self.assertAlmostEqual(expected, tcl.criterion_function(labels))
def test_entropy(self):
expected_values = [
([0, 1, 1, 1, 1, 1, 0, 0, 0, 1], 0.9709505944546686),
([0, 1, 1, 2, 2, 3, 4, 5, 3, 2, 1, 1], 0.9111886696810589),
([0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 2, 2, 2], 0.8120406807940999),
([0, 0, 1, 1, 1, 1, 0, 0], 1),
([0, 0, 1, 1, 2, 2, 3, 3], 1),
([0, 0, 1, 1, 1, 1, 1, 1], 0.8112781244591328),
([1], 0),
([0, 0, 0, 0], 0),
]
for labels, expected in expected_values:
self.assertAlmostEqual(expected, Splitter._entropy(labels))
tcl = self.build(criterion="entropy")
self.assertAlmostEqual(expected, tcl.criterion_function(labels))
def test_information_gain(self):
expected_values = [
(
[0, 1, 1, 1, 1, 1],
[0, 0, 0, 1],
0.16333333333333333,
0.25642589168200297,
),
(
[0, 1, 1, 2, 2, 3, 4, 5, 3, 2, 1, 1],
[5, 3, 2, 1, 1],
0.007381776239907684,
-0.03328610916207225,
),
([], [], 0.0, 0.0),
([1], [], 0.0, 0.0),
([], [1], 0.0, 0.0),
([0, 0, 0, 0], [0, 0], 0.0, 0.0),
([], [1, 1, 1, 2], 0.0, 0.0),
(None, [1, 2, 3], 0.0, 0.0),
([1, 2, 3], None, 0.0, 0.0),
]
for yu, yd, expected_gini, expected_entropy in expected_values:
yu = np.array(yu, dtype=np.int32) if yu is not None else None
yd = np.array(yd, dtype=np.int32) if yd is not None else None
if yu is not None and yd is not None:
complete = np.append(yu, yd)
elif yd is not None:
complete = yd
else:
complete = yu
tcl = self.build(criterion="gini")
computed = tcl.information_gain(complete, yu, yd)
self.assertAlmostEqual(expected_gini, computed)
tcl = self.build(criterion="entropy")
computed = tcl.information_gain(complete, yu, yd)
self.assertAlmostEqual(expected_entropy, computed)
def test_max_samples(self):
tcl = self.build(criteria="max_samples")
data = np.array(
[
[-0.1, 0.2, -0.3],
[0.7, 0.01, -0.1],
[0.7, -0.9, 0.5],
[0.1, 0.2, 0.3],
[-0.1, 0.2, 0.3],
[-0.1, 0.2, 0.3],
]
)
expected = data[:, 0]
y = [1, 2, 1, 0, 0, 0]
computed = tcl._max_samples(data, y)
self.assertEqual(0, computed)
computed_data = data[:, computed]
self.assertEqual((6,), computed_data.shape)
self.assertListEqual(expected.tolist(), computed_data.tolist())
def test_impurity(self):
tcl = self.build(criteria="impurity")
data = np.array(
[
[-0.1, 0.2, -0.3],
[0.7, 0.01, -0.1],
[0.7, -0.9, 0.5],
[0.1, 0.2, 0.3],
[-0.1, 0.2, 0.3],
[-0.1, 0.2, 0.3],
]
)
expected = data[:, 2]
y = np.array([1, 2, 1, 0, 0, 0])
computed = tcl._impurity(data, y)
self.assertEqual(2, computed)
computed_data = data[:, computed]
self.assertEqual((6,), computed_data.shape)
self.assertListEqual(expected.tolist(), computed_data.tolist())
def test_generate_subspaces(self):
features = 250
for max_features in range(2, features):
num = len(Splitter._generate_spaces(features, max_features))
self.assertEqual(5, num)
self.assertEqual(3, len(Splitter._generate_spaces(3, 2)))
self.assertEqual(4, len(Splitter._generate_spaces(4, 3)))
def test_best_splitter_few_sets(self):
X, y = load_iris(return_X_y=True)
X = np.delete(X, 3, 1)
tcl = self.build(splitter_type="best", random_state=self._random_state)
dataset, computed = tcl.get_subspace(X, y, max_features=2)
self.assertListEqual([0, 2], list(computed))
self.assertListEqual(X[:, computed].tolist(), dataset.tolist())
def test_splitter_parameter(self):
expected_values = [
[1, 4, 9, 12], # best entropy max_samples
[1, 3, 6, 10], # best entropy impurity
[6, 8, 10, 12], # best gini max_samples
[7, 8, 10, 11], # best gini impurity
[0, 3, 8, 12], # random entropy max_samples
[0, 3, 9, 11], # random entropy impurity
[0, 4, 7, 12], # random gini max_samples
[0, 2, 5, 6], # random gini impurity
]
X, y = load_wine(return_X_y=True)
rn = 0
for splitter_type in ["best", "random"]:
for criterion in ["entropy", "gini"]:
for criteria in [
"max_samples",
"impurity",
]:
tcl = self.build(
splitter_type=splitter_type,
criterion=criterion,
criteria=criteria,
)
expected = expected_values.pop(0)
random.seed(rn)
rn += 1
dataset, computed = tcl.get_subspace(X, y, max_features=4)
# print(
# "{}, # {:7s}{:8s}{:15s}".format(
# list(computed),
# splitter_type,
# criterion,
# criteria,
# )
# )
self.assertListEqual(expected, list(computed))
self.assertListEqual(
X[:, computed].tolist(), dataset.tolist()
)