def vl(dataground, subK=3, topNum=15):
"""Retrain a LDA model for subset"""
w_mi = dataground.subset_w_mi()
new_lda_model = LDA(K=subK, dictionary=dataground.dictionary)
new_lda_model.fit(w_mi)
sub_n_kt = new_lda_model.n_kt
topWordTokens = _top_words(sub_n_kt, topNum)
return topWordTokens
def load_data(self, corpus):
if self.dictionary is not None:
self.lda_model = LDA(dictionary=self.dictionary,
K=self.K,
n_early_stop=self.n_early_stop)
self.lda_model.fit(corpus)
else:
self.lda_model = LDA(K=self.K, n_early_stop=self.n_early_stop)
self.lda_model.fit(corpus,
min_df=self._min_df,
min_tf=self._min_tf,
max_dict_len=self._max_dict_len,
stem=self._stem)
self.dictionary = self.lda_model.dictionary
# self.target_subset_ids = range(int(self.lda_model.M / 20))
self.set_target_subset(range(int(self.lda_model.M / 20)),
random_state=0)
def vl(dataground, subK=5):
w_mi_train = dataground.subset_w_mi_train()
new_lda_model = LDA(K=subK, dictionary=dataground.dictionary)
new_lda_model.fit(w_mi_train)
sub_n_kt = new_lda_model.n_kt
return ReprModel(sub_n_kt)
class DataGround:
"""DataGround is used to store the corpus-level information"""
def __init__(self, K=100, n_early_stop=30, use_default_dict=False,
dict_file=None, min_tf=5, min_df=2, max_dict_len=8000,
stem=False, held_out_ratio=0.2):
self.K = K
self.n_early_stop = n_early_stop
self.held_out_ratio = held_out_ratio
if use_default_dict:
self.dictionary = Dictionary(dict_file=default_dict)
elif dict_file:
self.dictionary = Dictionary(dict_file=dict_file)
else:
self.dictionary = None
self._min_tf = min_tf
self._min_df = min_df
self._max_dict_len = max_dict_len
self._stem = stem
def load_data(self, corpus):
if self.dictionary is not None:
self.lda_model = LDA(dictionary=self.dictionary,
K=self.K,
n_early_stop=self.n_early_stop)
self.lda_model.fit(corpus)
else:
self.lda_model = LDA(K=self.K, n_early_stop=self.n_early_stop)
self.lda_model.fit(corpus,
min_df=self._min_df,
min_tf=self._min_tf,
max_dict_len=self._max_dict_len,
stem=self._stem)
self.dictionary = self.lda_model.dictionary
# self.target_subset_ids = range(int(self.lda_model.M / 20))
self.set_target_subset(range(int(self.lda_model.M / 20)),
random_state=0)
def _split(self, length, held_out_ratio=0.2, random_state=0):
train_length = int(length * (1 - held_out_ratio))
indexes = list(range(length))
random.seed(random_state)
random.shuffle(indexes)
train_index = indexes[:train_length]
test_index = indexes[train_length:]
return train_index, test_index
def set_target_subset(self, selected_ids, random_state=0):
self.target_subset_ids = selected_ids
subset_w_mi = self.subset_w_mi()
indexes = [self._split(len(doc), self.held_out_ratio, random_state)
for doc in subset_w_mi]
self.train_index = [x[0] for x in indexes]
self.test_index = [x[1] for x in indexes]
def subset_w_mi(self, with_dictionary=False):
subset_w_mi = [self.lda_model.w_mi[x] for x in self.target_subset_ids]
if with_dictionary:
return (subset_w_mi, self.dictionary)
else:
return subset_w_mi
def subset_w_mi_train(self):
subset_w_mi = [np.array(doc) for doc in self.subset_w_mi()]
subset_w_mi_train = [doc[index] for (doc, index)
in zip(subset_w_mi, self.train_index)]
return subset_w_mi_train
def subset_w_mi_test(self):
subset_w_mi = [np.array(doc) for doc in self.subset_w_mi()]
subset_w_mi_test = [doc[index] for (doc, index)
in zip(subset_w_mi, self.test_index)]
return subset_w_mi_test
def subset_z_mi(self):
lda_model = self.lda_model
z_mi = []
ids = self.target_subset_ids
for doc_id in ids:
start = lda_model.I_m[doc_id]
end = start + lda_model.N_m[doc_id]
z_mi.append(lda_model.Z[start:end])
return z_mi
def subset_z_mi_train(self):
subset_z_mi = self.subset_z_mi()
subset_z_mi_train = [z[index] for (z, index)
in zip(subset_z_mi, self.train_index)]
return subset_z_mi_train
def subset_z_mi_test(self):
subset_z_mi = self.subset_z_mi()
subset_z_mi_test = [z[index] for (z, index)
in zip(subset_z_mi, self.test_index)]
return subset_z_mi_test
def subset_n_mk(self):
n_mk = self.lda_model.n_mk
return n_mk[self.target_subset_ids]
def subset_n_mk_train(self):
z_mi_train = self.subset_z_mi_train()
M = len(z_mi_train)
n_mk_train = np.zeros((M, self.K))
for m in range(M):
for z_i in z_mi_train[m]:
n_mk_train[m, z_i] += 1
return n_mk_train
def subset_n_mk_test(self):
z_mi_test = self.subset_z_mi_test()
M = len(z_mi_test)
n_mk_test = np.zeros((M, self.K))
for m in range(M):
for z_i in z_mi_test[m]:
n_mk_test[m, z_i] += 1
return n_mk_test
import os
from mylda import LDA, demo_dataset_dir
filenames = [os.path.join(demo_dataset_dir, x)
for x in os.listdir(demo_dataset_dir)]
documents = [open(x, encoding="utf8").read() for x in filenames]
# Generate corpus-based dictionary
lda_model = LDA(K=5, n_early_stop=20)
lda_model.fit(documents, max_dict_len=5000, min_tf=5, stem=False)
lda_model.show_topic(topNum=15)
# Or use standalone dictionary
lda_model = LDA(K=5, n_early_stop=20, use_default_dict=True)
# You can also use your own dictionary
# lda_model = LDA(K=5, dict_file="yourdictionary.txt")
lda_model.fit(documents)
lda_model.show_topic(topNum=15)
