def undersampling(X, y, sampling_strategy='auto', n_neighbors=1):
sampler = OneSidedSelection(n_jobs=36,
sampling_strategy=sampling_strategy,
n_neighbors=n_neighbors)
X_us, y_us = sampler.fit_sample(X, y)
return X_us.copy(), y_us.copy()
def test_oss_sample_wrong_X():
"""Test either if an error is raised when X is different at fitting
and sampling"""
# Create the object
oss = OneSidedSelection(random_state=RND_SEED)
oss.fit(X, Y)
assert_raises(RuntimeError, oss.sample,
np.random.random((100, 40)), np.array([0] * 50 + [1] * 50))
def test_oss_sample_wrong_X():
"""Test either if an error is raised when X is different at fitting
and sampling"""
# Create the object
oss = OneSidedSelection(random_state=RND_SEED)
oss.fit(X, Y)
assert_raises(RuntimeError, oss.sample, np.random.random((100, 40)),
np.array([0] * 50 + [1] * 50))
def test_oss_fit_sample():
"""Test the fit sample routine"""
# Resample the data
oss = OneSidedSelection(random_state=RND_SEED)
X_resampled, y_resampled = oss.fit_sample(X, Y)
currdir = os.path.dirname(os.path.abspath(__file__))
X_gt = np.load(os.path.join(currdir, 'data', 'oss_x.npy'))
y_gt = np.load(os.path.join(currdir, 'data', 'oss_y.npy'))
assert_array_equal(X_resampled, X_gt)
assert_array_equal(y_resampled, y_gt)
def test_oss_fit_sample():
"""Test the fit sample routine"""
# Resample the data
oss = OneSidedSelection(random_state=RND_SEED)
X_resampled, y_resampled = oss.fit_sample(X, Y)
currdir = os.path.dirname(os.path.abspath(__file__))
X_gt = np.load(os.path.join(currdir, 'data', 'oss_x.npy'))
y_gt = np.load(os.path.join(currdir, 'data', 'oss_y.npy'))
assert_array_equal(X_resampled, X_gt)
assert_array_equal(y_resampled, y_gt)
def test_oss_fit():
"""Test the fitting method"""
# Create the object
oss = OneSidedSelection(random_state=RND_SEED)
# Fit the data
oss.fit(X, Y)
# Check if the data information have been computed
assert_equal(oss.min_c_, 0)
assert_equal(oss.maj_c_, 1)
assert_equal(oss.stats_c_[0], 6)
assert_equal(oss.stats_c_[1], 9)
def test_oss_fit_resample():
oss = OneSidedSelection(random_state=RND_SEED)
X_resampled, y_resampled = oss.fit_resample(X, Y)
X_gt = np.array([[-0.3879569, 0.6894251], [0.91542919, -0.65453327],
[-0.65571327, 0.42412021], [1.06446472, -1.09279772],
[0.30543283, -0.02589502], [-0.00717161, 0.00318087],
[-0.09322739, 1.28177189], [-0.77740357, 0.74097941],
[-0.43877303, 1.07366684], [-0.85795321, 0.82980738],
[-0.30126957, -0.66268378], [0.20246714, -0.34727125]])
y_gt = np.array([0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1])
assert_array_equal(X_resampled, X_gt)
assert_array_equal(y_resampled, y_gt)
def test_oss_fit():
"""Test the fitting method"""
# Create the object
oss = OneSidedSelection(random_state=RND_SEED)
# Fit the data
oss.fit(X, Y)
# Check if the data information have been computed
assert_equal(oss.min_c_, 0)
assert_equal(oss.maj_c_, 1)
assert_equal(oss.stats_c_[0], 6)
assert_equal(oss.stats_c_[1], 9)
def one_sided_selection(X,
y,
visualize=False,
pca2d=True,
pca3d=True,
tsne=True,
pie_evr=True):
oss = OneSidedSelection(random_state=42)
X_res, y_res = oss.fit_resample(X, y)
if visualize == True:
hist_over_and_undersampling(y_res)
pca_general(X_res, y_res, d2=pca2d, d3=pca3d, pie_evr=pie_evr)
return X_res, y_res
def test_multiclass_error():
""" Test either if an error is raised when the target are not binary
type. """
# continuous case
y = np.linspace(0, 1, 15)
oss = OneSidedSelection(random_state=RND_SEED)
assert_warns(UserWarning, oss.fit, X, y)
# multiclass case
y = np.array([0] * 10 + [1] * 3 + [2] * 2)
oss = OneSidedSelection(random_state=RND_SEED)
assert_warns(UserWarning, oss.fit, X, y)
def test_oss_fit_resample():
oss = OneSidedSelection(random_state=RND_SEED)
X_resampled, y_resampled = oss.fit_resample(X, Y)
X_gt = np.array([[-0.3879569, 0.6894251], [0.91542919, -0.65453327], [
-0.65571327, 0.42412021
], [1.06446472, -1.09279772], [0.30543283, -0.02589502], [
-0.00717161, 0.00318087
], [-0.09322739, 1.28177189], [-0.77740357, 0.74097941],
[-0.43877303, 1.07366684], [-0.85795321, 0.82980738],
[-0.30126957, -0.66268378], [0.20246714, -0.34727125]])
y_gt = np.array([0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1])
assert_array_equal(X_resampled, X_gt)
assert_array_equal(y_resampled, y_gt)
def use_OSSSMOTEENN(self):
X,y = preparation(self.path)
##############################
dy = pd.DataFrame(y)
dy.value_counts().plot(kind='bar',title='Count(label)')
plt.show()
#################################
oss = OneSidedSelection(random_state = 42,n_jobs=-1,sampling_strategy="majority")
X_res,y_res = oss.fit_sample(X,y)
dy_res = pd.DataFrame(y_res)
dy_res.value_counts().plot(kind='bar',title='Count(label)')
plt.show()
##############################
sme = SMOTEENN(random_state=42,n_jobs=-1)
X_sme, y_sme = sme.fit_sample(X_res, y_res)
#draw bar
dy_sme = pd.DataFrame(y_sme)
dy_sme.value_counts().plot(kind='bar',title='Count(label)')
plt.show()
#generate csv
df=pd.concat([X_sme,pd.DataFrame(y_sme)],axis=1)
df.to_csv(self.path.replace('.csv','_OSSSMOTEENN_Final_Test.csv') ,index = None,header=None,float_format='%.4f')
###the first line of data will be delete
##########draw PCA
pca = PCA(n_components=2)
X_sme = pca.fit_transform(X_sme)
plot_2d_space(X_sme,y_sme, 'SMOTE + ENN')
return self.path.replace('.csv','_OSSSMOTEENN_Final_Test.csv')
# if __name__ == '__main__':
# path ="++Final_Test++_pre.csv"
# #draw_bar(path)
# mhi = My_handle_imbalance(path)
# mhi.use_OSSSMOTEENN()
#
# #use_SMOTETomek(path)
# #draw_origin(path)
def test_oss_fit_sample_with_indices():
"""Test the fit sample routine with indices support"""
# Resample the data
oss = OneSidedSelection(return_indices=True, random_state=RND_SEED)
X_resampled, y_resampled, idx_under = oss.fit_sample(X, Y)
currdir = os.path.dirname(os.path.abspath(__file__))
X_gt = np.load(os.path.join(currdir, 'data', 'oss_x.npy'))
y_gt = np.load(os.path.join(currdir, 'data', 'oss_y.npy'))
idx_gt = np.load(os.path.join(currdir, 'data', 'oss_idx.npy'))
assert_array_equal(X_resampled, X_gt)
assert_array_equal(y_resampled, y_gt)
assert_array_equal(idx_under, idx_gt)
def test_oss_fit_sample_with_indices():
"""Test the fit sample routine with indices support"""
# Resample the data
oss = OneSidedSelection(return_indices=True, random_state=RND_SEED)
X_resampled, y_resampled, idx_under = oss.fit_sample(X, Y)
currdir = os.path.dirname(os.path.abspath(__file__))
X_gt = np.load(os.path.join(currdir, 'data', 'oss_x.npy'))
y_gt = np.load(os.path.join(currdir, 'data', 'oss_y.npy'))
idx_gt = np.load(os.path.join(currdir, 'data', 'oss_idx.npy'))
assert_array_equal(X_resampled, X_gt)
assert_array_equal(y_resampled, y_gt)
assert_array_equal(idx_under, idx_gt)
def test_oss_fit_sample_with_indices():
# Resample the data
oss = OneSidedSelection(return_indices=True, random_state=RND_SEED)
X_resampled, y_resampled, idx_under = oss.fit_sample(X, Y)
X_gt = np.array([[-0.3879569, 0.6894251], [0.91542919, -0.65453327],
[-0.65571327, 0.42412021], [1.06446472, -1.09279772],
[0.30543283, -0.02589502], [-0.00717161, 0.00318087],
[-0.09322739, 1.28177189], [-0.77740357, 0.74097941],
[-0.43877303, 1.07366684], [-0.85795321, 0.82980738],
[-0.30126957, -0.66268378], [0.20246714, -0.34727125]])
y_gt = np.array([0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1])
idx_gt = np.array([0, 3, 9, 12, 13, 14, 1, 2, 5, 6, 8, 11])
assert_array_equal(X_resampled, X_gt)
assert_array_equal(y_resampled, y_gt)
assert_array_equal(idx_under, idx_gt)
def test_oss_init():
# Define a ratio
oss = OneSidedSelection(random_state=RND_SEED)
assert_equal(oss.n_seeds_S, 1)
assert_equal(oss.n_jobs, 1)
assert_equal(oss.random_state, RND_SEED)
class ResamplingAlgorithms(Enum):
RO = ("Random Over-sampling", RandomOverSampler(random_state=1))
SMOTE = ("Smote", SMOTE(random_state=1))
ADASYN = ("ADASYN", ADASYN(random_state=1))
SMOTE_TL = ('SMOTE+TL', SMOTETomek(random_state=1))
SMOTE_ENN = ('SMOTE+ENN', SMOTEENN(random_state=1))
SMOTE_BOOST = ("SMOTEBoost", smote_boost.SMOTEBoost())
RU = ("Random Under-sampling", RandomUnderSampler(random_state=1))
CLUSTERCENTROIDS = ("ClusterCentroids", ClusterCentroids(random_state=1))
TOMEK_LINKS = ("TomekLinks", TomekLinks())
NM1 = ("NM1", NearMiss(version=1))
NM2 = ("NM2", NearMiss(version=2))
NM3 = ("NM3", NearMiss(version=3))
CNN = ("CNN", CondensedNearestNeighbour(random_state=1))
OSS = ("OneSidedSelection", OneSidedSelection(random_state=1))
ENN = ('ENN', EditedNearestNeighbours())
NCL = ('NCL', NeighbourhoodCleaningRule())
IHT = ('IHT', (InstanceHardnessThreshold(random_state=1)))
RENN = ('RENN', RepeatedEditedNearestNeighbours())
AllKNN = ('AllKNN', AllKNN())
@classmethod
def get_algorithm_by_name(cls, name):
filtered_algos = filter(lambda ra: ra.value[0] == name,
ResamplingAlgorithms)
return next(filtered_algos, ResamplingAlgorithms.RO)
def under_sampling(X, y, method):
if method == 'ClusterCentroids':
model = ClusterCentroids()
X_resampled, y_resampled = model.fit_resample(X, y)
elif method == 'RandomUnderSampler':
model = RandomUnderSampler()
X_resampled, y_resampled = model.fit_resample(X, y)
elif method == 'NearMiss':
model = NearMiss()
X_resampled, y_resampled = model.fit_resample(X, y)
elif method == 'EditedNearestNeighbours':
model = EditedNearestNeighbours()
X_resampled, y_resampled = model.fit_resample(X, y)
elif method == 'RepeatedEditedNearestNeighbours':
model = RepeatedEditedNearestNeighbours()
X_resampled, y_resampled = model.fit_resample(X, y)
elif method == 'AllKNN':
model = AllKNN()
X_resampled, y_resampled = model.fit_resample(X, y)
elif method == 'NeighbourhoodCleaningRule':
model = NeighbourhoodCleaningRule()
X_resampled, y_resampled = model.fit_resample(X, y)
elif method == 'OneSidedSelection':
model = OneSidedSelection()
X_resampled, y_resampled = model.fit_resample(X, y)
return X_resampled, y_resampled
def test_oss_with_wrong_object():
"""Test if an error is raised while passing a wrong object"""
# Resample the data
knn = 'rnd'
oss = OneSidedSelection(random_state=RND_SEED, n_neighbors=knn)
assert_raises(ValueError, oss.fit_sample, X, Y)
def resampling(train_data, train_labels, resampling_type, resampling_stragey):
train_data_new = np.reshape(train_data,
(train_data.shape[0], train_data.shape[1] *
train_data.shape[2] * train_data.shape[3]))
if resampling_type == 'SMOTE':
train_data_resampled, train_labels_resampled = SMOTE(
random_state=42).fit_resample(train_data_new, train_labels.values)
elif resampling_type == 'over_sampling':
over_sampler = RandomOverSampler(sampling_strategy=resampling_stragey)
train_data_resampled, train_labels_resampled = over_sampler.fit_resample(
train_data_new, train_labels.values)
elif resampling_type == 'under_sampling':
under_sampler = RandomUnderSampler(
sampling_strategy=resampling_stragey)
train_data_resampled, train_labels_resampled = under_sampler.fit_resample(
train_data_new, train_labels.values)
elif resampling_type == 'tomelinks':
t1 = TomekLinks(sampling_strategy=resampling_stragey)
train_data_resampled, train_labels_resampled = t1.fit_resample(
train_data_new, train_labels.values)
elif resampling_type == 'near_miss_neighbors':
undersample = NearMiss(version=1, n_neighbors=3)
train_data_resampled, train_labels_resampled = undersample.fit_resample(
train_data_new, train_labels.values)
elif resampling_type == 'one_sided_selection':
undersample = OneSidedSelection(n_neighbors=1, n_seeds_S=200)
train_data_resampled, train_labels_resampled = undersample.fit_resample(
train_data_new, train_labels.values)
return train_data_resampled, train_labels_resampled
def under_sample(X, y, sampler="RandomUnderSampler"):
# list of all samplers, in case you want to iterate all of them
samplers_list = ['RandomUnderSampler', 'ClusterCentroids', 'NearMiss', 'InstanceHardnessThreshold',
'CondensedNearestNeighbour', 'EditedNearestNeighbours', 'RepeatedEditedNearestNeighbours',
'AllKNN', 'NeighbourhoodCleaningRule', 'OneSidedSelection']
print(samplers_list)
# currently there is no parameters sampler
# this dict is used to choose a resampler by user. default is random
samplers = {
"RandomUnderSampler": RandomUnderSampler(),
"ClusterCentroids": ClusterCentroids(),
"NearMiss": NearMiss(),
"InstanceHardnessThreshold": InstanceHardnessThreshold(),
"CondensedNearestNeighbour": CondensedNearestNeighbour(),
"EditedNearestNeighbours": EditedNearestNeighbours(),
"RepeatedEditedNearestNeighbours": RepeatedEditedNearestNeighbours(),
"AllKNN": AllKNN(),
"NeighbourhoodCleaningRule": NeighbourhoodCleaningRule(),
"OneSidedSelection": OneSidedSelection(),
}
sampler = samplers[sampler]
# plot y class count before and after resample
print("before", sorted(Counter(y).items()))
# to resample simply call fit_resample method of sampler
X_resampled, y_resampled = sampler.fit_resample(X, y)
print("after", sorted(Counter(y_resampled).items()))
print('===' * 4, 'under_sample finished')
return X_resampled, y_resampled
def test_oss_sample_wt_fit():
"""Test either if an error is raised when sample is called before
fitting"""
# Create the object
oss = OneSidedSelection(random_state=RND_SEED)
assert_raises(RuntimeError, oss.sample, X, Y)
def make_clf(usx, usy, clf, clf_name, sampling, normalize=False):
'''
Function for the classification task - Trains and tests the classifier clf using 10-fold cross-validation
If normalize flag is True then the data are being normalised
The sampling parameter sets the type of sampling to be used
'''
print('----------{} with {}----------'.format(clf_name, sampling))
totalTP, totalFP, totalFN, totalTN = 0, 0, 0, 0
plot_ind = randint(0, 9)
j = 0
skf = StratifiedKFold(n_splits=10, shuffle=True)
for train_index, test_index in skf.split(usx, usy):
x_train, x_test = usx[train_index], usx[test_index]
y_train, y_test = usy[train_index], usy[test_index]
if sampling == 'SMOTE':
x_train, y_train = SMOTE(sampling_strategy=0.3).fit_resample(x_train, y_train)
elif sampling == 'ADASYN':
x_train, y_train = ADASYN(sampling_strategy=0.3).fit_resample(x_train, y_train)
elif sampling == 'ENN':
x_train, y_train = EditedNearestNeighbours().fit_resample(x_train, y_train)
elif sampling == 'Tomek':
x_train, y_train = TomekLinks().fit_resample(x_train, y_train)
elif sampling == 'SMOTETomek':
x_train, y_train = SMOTETomek(sampling_strategy=0.3).fit_resample(x_train, y_train)
elif sampling == 'SMOTEENN':
x_train, y_train = SMOTEENN(sampling_strategy=0.3).fit_resample(x_train, y_train)
elif sampling == 'NCR':
x_train, y_train = NeighbourhoodCleaningRule().fit_resample(x_train, y_train)
elif sampling == 'OSS':
x_train, y_train = OneSidedSelection().fit_resample(x_train, y_train)
if normalize:
scaler = StandardScaler().fit(x_train)
x_train = scaler.transform(x_train)
x_test = scaler.transform(x_test)
clf.fit(x_train, y_train)
# if plot_ind == j and clf_name == 'DecisionTreeClassifier':
# plot_decision_tree(clf)
y_predict = clf.predict(x_test)
for i in range(len(y_predict)):
if y_test[i] and y_predict[i]:
totalTP += 1
if not y_test[i] and y_predict[i]:
totalFP += 1
if y_test[i] and not y_predict[i]:
totalFN += 1
if not y_test[i] and not y_predict[i]:
totalTN += 1
j += 1
print('TOTAL TP: ' + str(totalTP))
print('TOTAL FP: ' + str(totalFP))
print('TOTAL FN: ' + str(totalFN))
print('TOTAL TN: ' + str(totalTN))
def under_sampling(self, data, label, n_neighbors=5, method=None):
#Input
# data: 2D array data (im_height*im_width, num of band)
# label: 1D array label(0,1,2...) per each data
# n_neighbors: num of neighbors used in OSS
# method: select under sampling method (OSS)
#Output
# return under sampled data, label
if method in self.under_method:
print("Before sampling label proportion: ",Counter(label))
if method == 'OSS' or method == 'OneSidedSelection':
undersample = OneSidedSelection(n_neighbors=n_neighbors, n_seeds_S=200)
data, label = undersample.fit_resample(data, label)
print("After sampling label proportion: ",Counter(label))
return data, label
def test_oss_fit_single_class():
"""Test either if an error when there is a single class"""
# Create the object
oss = OneSidedSelection(random_state=RND_SEED)
# Resample the data
# Create a wrong y
y_single_class = np.zeros((X.shape[0], ))
assert_warns(UserWarning, oss.fit, X, y_single_class)
def test_oss_init():
"""Test the initialisation of the object"""
# Define a ratio
oss = OneSidedSelection(random_state=RND_SEED)
assert_equal(oss.n_seeds_S, 1)
assert_equal(oss.n_jobs, 1)
assert_equal(oss.random_state, RND_SEED)
def test_oss_fit_sample_with_indices():
"""Test the fit sample routine with indices support"""
# Resample the data
oss = OneSidedSelection(return_indices=True, random_state=RND_SEED)
X_resampled, y_resampled, idx_under = oss.fit_sample(X, Y)
X_gt = np.array([[-0.3879569, 0.6894251], [0.91542919, -0.65453327],
[-0.65571327, 0.42412021], [1.06446472, -1.09279772],
[0.30543283, -0.02589502], [-0.00717161, 0.00318087],
[-0.09322739, 1.28177189], [-0.77740357, 0.74097941],
[-0.43877303, 1.07366684], [-0.85795321, 0.82980738],
[-0.30126957, -0.66268378], [0.20246714, -0.34727125]])
y_gt = np.array([0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1])
idx_gt = np.array([0, 3, 9, 12, 13, 14, 1, 2, 5, 6, 7, 10])
assert_array_equal(X_resampled, X_gt)
assert_array_equal(y_resampled, y_gt)
assert_array_equal(idx_under, idx_gt)
def resample(self, X, y, by, random_state=None, visualize=False):
'''
by: String
The method used to perform re-sampling
currently support: ['RUS', 'CNN', 'ENN', 'NCR', 'Tomek', 'ALLKNN', 'OSS',
'NM', 'CC', 'SMOTE', 'ADASYN', 'BorderSMOTE', 'SMOTEENN', 'SMOTETomek',
'ORG']
'''
if by == 'RUS':
sampler = RandomUnderSampler(random_state=random_state)
elif by == 'CNN':
sampler = CondensedNearestNeighbour(random_state=random_state)
elif by == 'ENN':
sampler = EditedNearestNeighbours(random_state=random_state)
elif by == 'NCR':
sampler = NeighbourhoodCleaningRule(random_state=random_state)
elif by == 'Tomek':
sampler = TomekLinks(random_state=random_state)
elif by == 'ALLKNN':
sampler = AllKNN(random_state=random_state)
elif by == 'OSS':
sampler = OneSidedSelection(random_state=random_state)
elif by == 'NM':
sampler = NearMiss(random_state=random_state)
elif by == 'CC':
sampler = ClusterCentroids(random_state=random_state)
elif by == 'SMOTE':
sampler = SMOTE(random_state=random_state)
elif by == 'ADASYN':
sampler = ADASYN(random_state=random_state)
elif by == 'BorderSMOTE':
sampler = BorderlineSMOTE(random_state=random_state)
elif by == 'SMOTEENN':
sampler = SMOTEENN(random_state=random_state)
elif by == 'SMOTETomek':
sampler = SMOTETomek(random_state=random_state)
elif by == 'ORG':
sampler = None
else:
raise Error('Unexpected \'by\' type {}'.format(by))
if by != 'ORG':
X_train, y_train = sampler.fit_resample(X, y)
else:
X_train, y_train = X, y
if visualize:
df = pd.DataFrame(X_train)
df['label'] = y_train
df.plot.scatter(x=0,
y=1,
c='label',
s=3,
colormap='coolwarm',
title='{} training set'.format(by))
return X_train, y_train
def get_under_sample_models():
models, names = list(), list()
models.append(TomekLinks())
names.append('TomesLinks')
models.append(EditedNearestNeighbours())
names.append('EditedNearestNeighbors')
models.append(RepeatedEditedNearestNeighbours())
names.append('RENN')
models.append(OneSidedSelection())
names.append('OneSidedSelection')
models.append(NeighbourhoodCleaningRule())
names.append('NCR')
return models, names
def test_oss_with_object():
"""Test the fit sample routine with an knn object"""
# Resample the data
knn = KNeighborsClassifier(n_neighbors=1)
oss = OneSidedSelection(random_state=RND_SEED, n_neighbors=knn)
X_resampled, y_resampled = oss.fit_sample(X, Y)
X_gt = np.array([[-0.3879569, 0.6894251], [0.91542919, -0.65453327],
[-0.65571327, 0.42412021], [1.06446472, -1.09279772],
[0.30543283, -0.02589502], [-0.00717161, 0.00318087],
[-0.09322739, 1.28177189], [-0.77740357, 0.74097941],
[-0.43877303, 1.07366684], [-0.85795321, 0.82980738],
[-0.30126957, -0.66268378], [0.20246714, -0.34727125]])
y_gt = np.array([0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1])
assert_array_equal(X_resampled, X_gt)
assert_array_equal(y_resampled, y_gt)
# Resample the data
knn = 1
oss = OneSidedSelection(random_state=RND_SEED, n_neighbors=knn)
X_resampled, y_resampled = oss.fit_sample(X, Y)
assert_array_equal(X_resampled, X_gt)
assert_array_equal(y_resampled, y_gt)
def resample(self, X, y, by, random_state=None):
'''
by: String
The method used to perform re-sampling
currently support: ['RUS', 'CNN', 'ENN', 'NCR', 'Tomek', 'ALLKNN', 'OSS',
'NM', 'CC', 'SMOTE', 'ADASYN', 'BorderSMOTE', 'SMOTEENN', 'SMOTETomek',
'ORG']
'''
if by == 'RUS':
sampler = RandomUnderSampler(random_state=random_state)
elif by == 'CNN':
sampler = CondensedNearestNeighbour(random_state=random_state)
elif by == 'ENN':
sampler = EditedNearestNeighbours(random_state=random_state)
elif by == 'NCR':
sampler = NeighbourhoodCleaningRule(random_state=random_state)
elif by == 'Tomek':
sampler = TomekLinks(random_state=random_state)
elif by == 'ALLKNN':
sampler = AllKNN(random_state=random_state)
elif by == 'OSS':
sampler = OneSidedSelection(random_state=random_state)
elif by == 'NM':
sampler = NearMiss(random_state=random_state)
elif by == 'CC':
sampler = ClusterCentroids(random_state=random_state)
elif by == 'ROS':
sampler = RandomOverSampler(random_state=random_state)
elif by == 'SMOTE':
sampler = SMOTE(random_state=random_state)
elif by == 'ADASYN':
sampler = ADASYN(random_state=random_state)
elif by == 'BorderSMOTE':
sampler = BorderlineSMOTE(random_state=random_state)
elif by == 'SMOTEENN':
sampler = SMOTEENN(random_state=random_state)
elif by == 'SMOTETomek':
sampler = SMOTETomek(random_state=random_state)
elif by == 'ORG':
sampler = None
else:
raise Error('Unexpected \'by\' type {}'.format(by))
if by != 'ORG':
X_train, y_train = sampler.fit_resample(X, y)
else:
X_train, y_train = X, y
return X_train, y_train
def test_oss_init():
"""Test the initialisation of the object"""
# Define a ratio
verbose = True
oss = OneSidedSelection(random_state=RND_SEED, verbose=verbose)
assert_equal(oss.size_ngh, 1)
assert_equal(oss.n_seeds_S, 1)
assert_equal(oss.n_jobs, -1)
assert_equal(oss.random_state, RND_SEED)
assert_equal(oss.verbose, verbose)
assert_equal(oss.min_c_, None)
assert_equal(oss.maj_c_, None)
assert_equal(oss.stats_c_, {})
def UnderSample(X, Y, method='Random', random_state=42):
if X.size == len(X):
X = X.reshape(-1, 1)
if method is 'Cluster': # 默认kmeans估计器
sampler = ClusterCentroids(ratio='auto',
random_state=random_state,
estimator=None)
elif method is 'Random':
sampler = RandomUnderSampler(ratio='auto',
random_state=random_state,
replacement=False)
elif method is 'NearMiss_1':
sampler = NearMiss(ratio='auto', random_state=random_state, version=1)
elif method is 'NearMiss_2':
sampler = NearMiss(ratio='auto', random_state=random_state, version=2)
elif method is 'NearMiss_3':
sampler = NearMiss(ratio='auto', random_state=random_state, version=3)
elif method is 'TomekLinks':
sampler = TomekLinks(ratio='auto', random_state=random_state)
elif method is 'ENN': # kind_sel可取'all'和'mode'
sampler = EditedNearestNeighbours(ratio='auto',
random_state=random_state,
kind_sel='all')
elif method is 'RENN': # kind_sel可取'all'和'mode'
sampler = RepeatedEditedNearestNeighbours(ratio='auto',
random_state=random_state,
kind_sel='all')
elif method is 'All_KNN':
sampler = AllKNN(ratio='auto',
random_state=random_state,
kind_sel='all')
elif method is 'CNN':
sampler = CondensedNearestNeighbour(ratio='auto',
random_state=random_state)
elif method is 'One_SS':
sampler = OneSidedSelection(ratio='auto', random_state=random_state)
elif method is 'NCR':
sampler = NeighbourhoodCleaningRule(ratio='auto',
random_state=random_state,
kind_sel='all',
threshold_cleaning=0.5)
elif method is 'IHT':
sampler = InstanceHardnessThreshold(estimator=None,
ratio='auto',
random_state=random_state)
X_resampled, Y_resampled = sampler.fit_sample(X, Y)
return X_resampled, Y_resampled
def under_sampling_algs():
algs = list()
algs.append(("No Rs Undersampling case", "No Re-sampling"))
algs.append((RandomUnderSampler(random_state=1), 'RU'))
algs.append((ClusterCentroids(random_state=1), 'CC'))
algs.append((TomekLinks(), 'TL'))
algs.append((NearMiss(version=1), 'NM1'))
algs.append((NearMiss(version=2), 'NM2'))
algs.append((NearMiss(version=3), 'NM3'))
algs.append((CondensedNearestNeighbour(random_state=1), 'CNN'))
algs.append((OneSidedSelection(random_state=1), 'OSS'))
algs.append((EditedNearestNeighbours(), 'ENN'))
algs.append((NeighbourhoodCleaningRule(), 'NCL'))
algs.append((InstanceHardnessThreshold(random_state=1), 'IHT'))
algs.append((RepeatedEditedNearestNeighbours(), 'RENN'))
algs.append((AllKNN(), 'AllKNN'))
return algs
def equalize_training_dataset_with_OneSidedSel(x_train, y_train):
from imblearn.under_sampling import OneSidedSelection
old_shape = list(x_train.shape)
# reshape before using using over/undersampling method
x_tmp = np.reshape(x_train, (x_train.shape[0], -1))
x_resampled, y_resampled = OneSidedSelection(
sampling_strategy={i: 180
for i in range(0, 43)},
n_seeds_S=5,
n_jobs=8).fit_resample(x_tmp, y_train)
print(sorted(Counter(y_resampled).items()))
# reshape after using using over/undersampling method
old_shape[0] = x_resampled.shape[0]
x_resampled = np.reshape(x_resampled, tuple(old_shape))
return x_resampled, y_resampled
def get_models():
models, names = list(), list()
# TL
models.append(TomekLinks())
names.append('TL')
# ENN
models.append(EditedNearestNeighbours())
names.append('ENN')
# RENN
models.append(RepeatedEditedNearestNeighbours())
names.append('RENN')
# OSS
models.append(OneSidedSelection())
names.append('OSS')
# NCR
models.append(NeighbourhoodCleaningRule())
names.append('NCR')
return models, names
def get_samplers():
samplers = {
# Under-samplers
'RandomUn': RandomUnderSampler(),
'TL': TomekLinks(),
# 'ENN': EditedNearestNeighbours(),
'RENN': RepeatedEditedNearestNeighbours(),
'OSS': OneSidedSelection(),
'NCR': NeighbourhoodCleaningRule(),
'IHT': InstanceHardnessThreshold(),
# Over-Samplers
'RandomOv': RandomOverSampler(),
'SMOTE': SMOTE(),
'SMOTESVM': SVMSMOTE(),
# 'SMOTEKMeans': KMeansSMOTE(),
'ADASYN': ADASYN(),
# Combined Under and Over Samplers
'SMOTEENN': SMOTEENN(enn=EditedNearestNeighbours(sampling_strategy='majority')),
'SMOTETomek': SMOTETomek(tomek=TomekLinks(sampling_strategy='majority')),
}
return samplers
print(__doc__)
# Generate the dataset
X, y = make_classification(n_classes=2, class_sep=2, weights=[0.1, 0.9],
n_informative=3, n_redundant=1, flip_y=0,
n_features=20, n_clusters_per_class=1,
n_samples=200, random_state=10)
# Instanciate a PCA object for the sake of easy visualisation
pca = PCA(n_components=2)
# Fit and transform x to visualise inside a 2D feature space
X_vis = pca.fit_transform(X)
# Apply One-Sided Selection
oss = OneSidedSelection(return_indices=True)
X_resampled, y_resampled, idx_resampled = oss.fit_resample(X, y)
X_res_vis = pca.transform(X_resampled)
fig = plt.figure()
ax = fig.add_subplot(1, 1, 1)
idx_samples_removed = np.setdiff1d(np.arange(X_vis.shape[0]),
idx_resampled)
idx_class_0 = y_resampled == 0
plt.scatter(X_res_vis[idx_class_0, 0], X_res_vis[idx_class_0, 1],
alpha=.8, label='Class #0')
plt.scatter(X_res_vis[~idx_class_0, 0], X_res_vis[~idx_class_0, 1],
alpha=.8, label='Class #1')
plt.scatter(X_vis[idx_samples_removed, 0], X_vis[idx_samples_removed, 1],
palette = sns.color_palette()
# Generate the dataset
X, y = make_classification(n_classes=2, class_sep=2, weights=[0.1, 0.9],
n_informative=3, n_redundant=1, flip_y=0,
n_features=20, n_clusters_per_class=1,
n_samples=5000, random_state=10)
# Instanciate a PCA object for the sake of easy visualisation
pca = PCA(n_components=2)
# Fit and transform x to visualise inside a 2D feature space
X_vis = pca.fit_transform(X)
# Apply One-Sided Selection
oss = OneSidedSelection()
X_resampled, y_resampled = oss.fit_sample(X, y)
X_res_vis = pca.transform(X_resampled)
# Two subplots, unpack the axes array immediately
f, (ax1, ax2) = plt.subplots(1, 2)
ax1.scatter(X_vis[y == 0, 0], X_vis[y == 0, 1], label="Class #0", alpha=0.5,
edgecolor=almost_black, facecolor=palette[0], linewidth=0.15)
ax1.scatter(X_vis[y == 1, 0], X_vis[y == 1, 1], label="Class #1", alpha=0.5,
edgecolor=almost_black, facecolor=palette[2], linewidth=0.15)
ax1.set_title('Original set')
ax2.scatter(X_res_vis[y_resampled == 0, 0], X_res_vis[y_resampled == 0, 1],
label="Class #0", alpha=.5, edgecolor=almost_black,
facecolor=palette[0], linewidth=0.15)
def test_oss_with_wrong_object():
knn = 'rnd'
oss = OneSidedSelection(random_state=RND_SEED, n_neighbors=knn)
with raises(ValueError, match="has to be a int"):
oss.fit_resample(X, Y)
