def fit(self,
topK=50,
shrink=100,
similarity='cosine',
normalize=True,
feature_weighting="none",
**similarity_args):
self.topK = topK
self.shrink = shrink
if feature_weighting not in self.FEATURE_WEIGHTING_VALUES:
raise ValueError(
"Value for 'feature_weighting' not recognized. Acceptable values are {}, provided was '{}'"
.format(self.FEATURE_WEIGHTING_VALUES, feature_weighting))
if feature_weighting == "BM25":
self.URM_train = self.URM_train.astype(np.float32)
self.URM_train = okapi_BM_25(self.URM_train.T).T
self.URM_train = check_matrix(self.URM_train, 'csr')
elif feature_weighting == "TF-IDF":
self.URM_train = self.URM_train.astype(np.float32)
self.URM_train = TF_IDF(self.URM_train.T).T
self.URM_train = check_matrix(self.URM_train, 'csr')
similarity = Compute_Similarity(self.URM_train.T,
shrink=shrink,
topK=topK,
normalize=normalize,
similarity=similarity,
**similarity_args)
self.W_sparse = similarity.compute_similarity()
self.W_sparse = check_matrix(self.W_sparse, format='csr')
def _compute_W_sparse(self, use_incremental=False):
if use_incremental:
feature_weights = self.D_incremental
else:
feature_weights = self.D_best
self.similarity = Compute_Similarity(
self.ICM.T,
shrink=0,
topK=self.topK,
normalize=self.normalize_similarity,
row_weights=feature_weights)
self.W_sparse = self.similarity.compute_similarity()
self.sparse_weights = True
def _generateTrainData_low_ram(self):
print(self.RECOMMENDER_NAME + ": Generating train data")
start_time_batch = time.time()
# Here is important only the structure
self.similarity = Compute_Similarity(self.ICM.T,
shrink=0,
topK=self.topK,
normalize=False)
S_matrix_contentKNN = self.similarity.compute_similarity()
S_matrix_contentKNN = check_matrix(S_matrix_contentKNN, "csr")
self._writeLog(
self.RECOMMENDER_NAME +
": Collaborative S density: {:.2E}, nonzero cells {}".format(
self.S_matrix_target.nnz /
self.S_matrix_target.shape[0]**2, self.S_matrix_target.nnz))
self._writeLog(
self.RECOMMENDER_NAME +
": Content S density: {:.2E}, nonzero cells {}".format(
S_matrix_contentKNN.nnz /
S_matrix_contentKNN.shape[0]**2, S_matrix_contentKNN.nnz))
if self.normalize_similarity:
# Compute sum of squared
sum_of_squared_features = np.array(
self.ICM.T.power(2).sum(axis=0)).ravel()
sum_of_squared_features = np.sqrt(sum_of_squared_features)
num_common_coordinates = 0
estimated_n_samples = int(S_matrix_contentKNN.nnz *
(1 + self.add_zeros_quota) * 1.2)
self.row_list = np.zeros(estimated_n_samples, dtype=np.int32)
self.col_list = np.zeros(estimated_n_samples, dtype=np.int32)
self.data_list = np.zeros(estimated_n_samples, dtype=np.float64)
num_samples = 0
for row_index in range(self.n_items):
start_pos_content = S_matrix_contentKNN.indptr[row_index]
end_pos_content = S_matrix_contentKNN.indptr[row_index + 1]
content_coordinates = S_matrix_contentKNN.indices[
start_pos_content:end_pos_content]
start_pos_target = self.S_matrix_target.indptr[row_index]
end_pos_target = self.S_matrix_target.indptr[row_index + 1]
target_coordinates = self.S_matrix_target.indices[
start_pos_target:end_pos_target]
# Chech whether the content coordinate is associated to a non zero target value
# If true, the content coordinate has a collaborative non-zero value
# if false, the content coordinate has a collaborative zero value
is_common = np.in1d(content_coordinates, target_coordinates)
num_common_in_current_row = is_common.sum()
num_common_coordinates += num_common_in_current_row
for index in range(len(is_common)):
if num_samples == estimated_n_samples:
dataBlock = 1000000
self.row_list = np.concatenate(
(self.row_list, np.zeros(dataBlock, dtype=np.int32)))
self.col_list = np.concatenate(
(self.col_list, np.zeros(dataBlock, dtype=np.int32)))
self.data_list = np.concatenate(
(self.data_list, np.zeros(dataBlock,
dtype=np.float64)))
if is_common[index]:
# If cell exists in target matrix, add its value
# Otherwise it will remain zero with a certain probability
col_index = content_coordinates[index]
self.row_list[num_samples] = row_index
self.col_list[num_samples] = col_index
new_data_value = self.S_matrix_target[row_index, col_index]
if self.normalize_similarity:
new_data_value *= sum_of_squared_features[
row_index] * sum_of_squared_features[col_index]
self.data_list[num_samples] = new_data_value
num_samples += 1
elif np.random.rand() <= self.add_zeros_quota:
col_index = content_coordinates[index]
self.row_list[num_samples] = row_index
self.col_list[num_samples] = col_index
self.data_list[num_samples] = 0.0
num_samples += 1
if time.time(
) - start_time_batch > 30 or num_samples == S_matrix_contentKNN.nnz * (
1 + self.add_zeros_quota):
print(self.RECOMMENDER_NAME +
": Generating train data. Sample {} ( {:.2f} %) ".format(
num_samples, num_samples / S_matrix_contentKNN.nnz *
(1 + self.add_zeros_quota) * 100))
sys.stdout.flush()
sys.stderr.flush()
start_time_batch = time.time()
self._writeLog(
self.RECOMMENDER_NAME +
": Content S structure has {} out of {} ( {:.2f}%) nonzero collaborative cells"
.format(num_common_coordinates, S_matrix_contentKNN.nnz,
num_common_coordinates / S_matrix_contentKNN.nnz * 100))
# Discard extra cells at the left of the array
self.row_list = self.row_list[:num_samples]
self.col_list = self.col_list[:num_samples]
self.data_list = self.data_list[:num_samples]
data_nnz = sum(np.array(self.data_list) != 0)
data_sum = sum(self.data_list)
collaborative_nnz = self.S_matrix_target.nnz
collaborative_sum = sum(self.S_matrix_target.data)
self._writeLog(
self.RECOMMENDER_NAME +
": Nonzero collaborative cell sum is: {:.2E}, average is: {:.2E}, "
"average over all collaborative data is {:.2E}".format(
data_sum, data_sum / data_nnz, collaborative_sum /
collaborative_nnz))
class CFW_D_Similarity_Linalg(BaseItemSimilarityMatrixRecommender):
RECOMMENDER_NAME = "CFW_D_Similarity_Linalg"
def __init__(self, URM_train, ICM, S_matrix_target):
super(CFW_D_Similarity_Linalg, self).__init__(URM_train)
if (URM_train.shape[1] != ICM.shape[0]):
raise ValueError(
"Number of items not consistent. URM contains {} but ICM contains {}"
.format(URM_train.shape[1], ICM.shape[0]))
if (S_matrix_target.shape[0] != S_matrix_target.shape[1]):
raise ValueError(
"Items imilarity matrix is not square: rows are {}, columns are {}"
.format(S_matrix_target.shape[0], S_matrix_target.shape[1]))
if (S_matrix_target.shape[0] != ICM.shape[0]):
raise ValueError(
"Number of items not consistent. S_matrix contains {} but ICM contains {}"
.format(S_matrix_target.shape[0], ICM.shape[0]))
self.S_matrix_target = check_matrix(S_matrix_target, 'csr')
self.ICM = check_matrix(ICM, 'csr')
self.n_items = self.URM_train.shape[1]
self.n_users = self.URM_train.shape[0]
self.n_features = self.ICM.shape[1]
self.sparse_weights = True
def _writeLog(self, string):
print(string)
sys.stdout.flush()
sys.stderr.flush()
if self.logFile is not None:
self.logFile.write(string + "\n")
self.logFile.flush()
def _generateTrainData_low_ram(self):
print(self.RECOMMENDER_NAME + ": Generating train data")
start_time_batch = time.time()
# Here is important only the structure
self.similarity = Compute_Similarity(self.ICM.T,
shrink=0,
topK=self.topK,
normalize=False)
S_matrix_contentKNN = self.similarity.compute_similarity()
S_matrix_contentKNN = check_matrix(S_matrix_contentKNN, "csr")
self._writeLog(
self.RECOMMENDER_NAME +
": Collaborative S density: {:.2E}, nonzero cells {}".format(
self.S_matrix_target.nnz /
self.S_matrix_target.shape[0]**2, self.S_matrix_target.nnz))
self._writeLog(
self.RECOMMENDER_NAME +
": Content S density: {:.2E}, nonzero cells {}".format(
S_matrix_contentKNN.nnz /
S_matrix_contentKNN.shape[0]**2, S_matrix_contentKNN.nnz))
if self.normalize_similarity:
# Compute sum of squared
sum_of_squared_features = np.array(
self.ICM.T.power(2).sum(axis=0)).ravel()
sum_of_squared_features = np.sqrt(sum_of_squared_features)
num_common_coordinates = 0
estimated_n_samples = int(S_matrix_contentKNN.nnz *
(1 + self.add_zeros_quota) * 1.2)
self.row_list = np.zeros(estimated_n_samples, dtype=np.int32)
self.col_list = np.zeros(estimated_n_samples, dtype=np.int32)
self.data_list = np.zeros(estimated_n_samples, dtype=np.float64)
num_samples = 0
for row_index in range(self.n_items):
start_pos_content = S_matrix_contentKNN.indptr[row_index]
end_pos_content = S_matrix_contentKNN.indptr[row_index + 1]
content_coordinates = S_matrix_contentKNN.indices[
start_pos_content:end_pos_content]
start_pos_target = self.S_matrix_target.indptr[row_index]
end_pos_target = self.S_matrix_target.indptr[row_index + 1]
target_coordinates = self.S_matrix_target.indices[
start_pos_target:end_pos_target]
# Chech whether the content coordinate is associated to a non zero target value
# If true, the content coordinate has a collaborative non-zero value
# if false, the content coordinate has a collaborative zero value
is_common = np.in1d(content_coordinates, target_coordinates)
num_common_in_current_row = is_common.sum()
num_common_coordinates += num_common_in_current_row
for index in range(len(is_common)):
if num_samples == estimated_n_samples:
dataBlock = 1000000
self.row_list = np.concatenate(
(self.row_list, np.zeros(dataBlock, dtype=np.int32)))
self.col_list = np.concatenate(
(self.col_list, np.zeros(dataBlock, dtype=np.int32)))
self.data_list = np.concatenate(
(self.data_list, np.zeros(dataBlock,
dtype=np.float64)))
if is_common[index]:
# If cell exists in target matrix, add its value
# Otherwise it will remain zero with a certain probability
col_index = content_coordinates[index]
self.row_list[num_samples] = row_index
self.col_list[num_samples] = col_index
new_data_value = self.S_matrix_target[row_index, col_index]
if self.normalize_similarity:
new_data_value *= sum_of_squared_features[
row_index] * sum_of_squared_features[col_index]
self.data_list[num_samples] = new_data_value
num_samples += 1
elif np.random.rand() <= self.add_zeros_quota:
col_index = content_coordinates[index]
self.row_list[num_samples] = row_index
self.col_list[num_samples] = col_index
self.data_list[num_samples] = 0.0
num_samples += 1
if time.time(
) - start_time_batch > 30 or num_samples == S_matrix_contentKNN.nnz * (
1 + self.add_zeros_quota):
print(self.RECOMMENDER_NAME +
": Generating train data. Sample {} ( {:.2f} %) ".format(
num_samples, num_samples / S_matrix_contentKNN.nnz *
(1 + self.add_zeros_quota) * 100))
sys.stdout.flush()
sys.stderr.flush()
start_time_batch = time.time()
self._writeLog(
self.RECOMMENDER_NAME +
": Content S structure has {} out of {} ( {:.2f}%) nonzero collaborative cells"
.format(num_common_coordinates, S_matrix_contentKNN.nnz,
num_common_coordinates / S_matrix_contentKNN.nnz * 100))
# Discard extra cells at the left of the array
self.row_list = self.row_list[:num_samples]
self.col_list = self.col_list[:num_samples]
self.data_list = self.data_list[:num_samples]
data_nnz = sum(np.array(self.data_list) != 0)
data_sum = sum(self.data_list)
collaborative_nnz = self.S_matrix_target.nnz
collaborative_sum = sum(self.S_matrix_target.data)
self._writeLog(
self.RECOMMENDER_NAME +
": Nonzero collaborative cell sum is: {:.2E}, average is: {:.2E}, "
"average over all collaborative data is {:.2E}".format(
data_sum, data_sum / data_nnz, collaborative_sum /
collaborative_nnz))
def fit(self,
show_max_performance=False,
logFile=None,
loss_tolerance=1e-6,
iteration_limit=50000,
damp_coeff=0.0,
topK=300,
add_zeros_quota=0.0,
normalize_similarity=False):
self.logFile = logFile
self.normalize_similarity = normalize_similarity
self.add_zeros_quota = add_zeros_quota
self.topK = topK
self._generateTrainData_low_ram()
commonFeatures = self.ICM[self.row_list].multiply(
self.ICM[self.col_list])
linalg_result = linalg.lsqr(commonFeatures,
self.data_list,
show=False,
atol=loss_tolerance,
btol=loss_tolerance,
iter_lim=iteration_limit,
damp=damp_coeff)
# res = linalg.lsmr(commonFeatures, self.data_list, show = False, atol=loss_tolerance, btol=loss_tolerance,
# maxiter = iteration_limit, damp=damp_coeff)
self.D_incremental = linalg_result[0].copy()
self.D_best = linalg_result[0].copy()
self.epochs_best = 0
self.loss = linalg_result[3]
self._compute_W_sparse()
def _compute_W_sparse(self, use_incremental=False):
if use_incremental:
feature_weights = self.D_incremental
else:
feature_weights = self.D_best
self.similarity = Compute_Similarity(
self.ICM.T,
shrink=0,
topK=self.topK,
normalize=self.normalize_similarity,
row_weights=feature_weights)
self.W_sparse = self.similarity.compute_similarity()
self.sparse_weights = True
def save_model(self, folder_path, file_name=None):
import pickle
if file_name is None:
file_name = self.RECOMMENDER_NAME
print("{}: Saving model in file '{}'".format(self.RECOMMENDER_NAME,
folder_path + file_name))
dictionary_to_save = {
"D_best": self.D_best,
"topK": self.topK,
"sparse_weights": self.sparse_weights,
"W_sparse": self.W_sparse,
"normalize_similarity": self.normalize_similarity
}
pickle.dump(dictionary_to_save,
open(folder_path + file_name, "wb"),
protocol=pickle.HIGHEST_PROTOCOL)
print("{}: Saving complete".format(self.RECOMMENDER_NAME))